- A
Containerize the entire monolithic application and deploy it on Google Kubernetes Engine with a persistent volume for the database, with horizontal pod autoscaling.
Why wrong: Containerization requires development effort; the database in a persistent volume is not horizontally scalable.
- B
Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with continuous replication for minimal downtime. Simultaneously, rehost the application on a managed instance group with autoscaling. Have a rollback plan.
Continuous replication minimizes downtime, MIG provides autoscaling, and rollback plan ensures safety.
- C
Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with a one-time dump and restore, and rehost the application on a single Compute Engine instance.
Why wrong: One-time dump and restore causes significant downtime, and a single instance does not provide autoscaling.
- D
Refactor the monolithic application into microservices, deploy on Cloud Run, and use Cloud Spanner for the database.
Why wrong: Refactoring is a major rewrite, violating the constraint, and Cloud Spanner may be overkill.
Cloud Digital Leader Why cloud technology is transforming business Practice Question
This GCDL practice question tests your understanding of why cloud technology is transforming business. The scenario asks you to isolate a root cause — eliminate options that address a different problem before choosing. After answering, compare your reasoning against the explanation and wrong-answer breakdown below. Once you have made your selection, read the full explanation to reinforce the concept and understand why each distractor is designed to mislead on exam day.
A mid-sized company runs a legacy inventory management system on a single on-premises server. The system uses a monolithic Java application and a PostgreSQL database. The server has reached 90% CPU usage during business hours, and the database is 800 GB. The company wants to migrate to Google Cloud to take advantage of autoscaling and reduce hardware costs. The migration must have minimal downtime and the application cannot be significantly rewritten. The team also wants to enable future scalability for peak seasons. The IT team includes experienced database administrators but limited application development resources. Given the constraints, which approach should the team take?
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with continuous replication for minimal downtime. Simultaneously, rehost the application on a managed instance group with autoscaling. Have a rollback plan.
Option B is correct because it combines Database Migration Service with continuous replication (CDC) to achieve near-zero downtime for the 800 GB PostgreSQL database, while rehosting the monolithic application on a managed instance group with autoscaling to address CPU spikes without code changes. This approach respects the constraint of limited app development resources by avoiding refactoring, and the rollback plan provides safety during migration.
Key principle: Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Containerize the entire monolithic application and deploy it on Google Kubernetes Engine with a persistent volume for the database, with horizontal pod autoscaling.
Why it's wrong here
Containerization requires development effort; the database in a persistent volume is not horizontally scalable.
- ✓
Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with continuous replication for minimal downtime. Simultaneously, rehost the application on a managed instance group with autoscaling. Have a rollback plan.
Why this is correct
Continuous replication minimizes downtime, MIG provides autoscaling, and rollback plan ensures safety.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with a one-time dump and restore, and rehost the application on a single Compute Engine instance.
Why it's wrong here
One-time dump and restore causes significant downtime, and a single instance does not provide autoscaling.
- ✗
Refactor the monolithic application into microservices, deploy on Cloud Run, and use Cloud Spanner for the database.
Why it's wrong here
Refactoring is a major rewrite, violating the constraint, and Cloud Spanner may be overkill.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Google Cloud often tests the misconception that containerization (GKE) is always the best path to scalability, but here the constraints (no rewrite, limited dev resources) make rehosting on MIGs with Database Migration Service the pragmatic choice, not the most architecturally 'modern' one.
Detailed technical explanation
How to think about this question
Database Migration Service uses PostgreSQL logical replication (pglogical or native publication/subscription) to stream changes continuously, allowing the source database to remain online until cutover; this is critical for minimizing downtime on large databases. Managed instance groups (MIGs) use instance templates and autoscalers to add/remove VMs based on CPU utilization, directly addressing the 90% CPU issue without code changes, and can be paired with a TCP/UDP load balancer for session persistence.
KKey Concepts to Remember
- Read the scenario before looking for a memorised answer.
- Find the constraint that changes the correct option.
- Eliminate answers that are true in general but not in this case.
TExam Day Tips
- Watch for words such as best, first, most likely and least administrative effort.
- Review why wrong options are wrong, not only why the correct option is correct.
Key takeaway
Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option.
Real-world example
How this comes up in practice
A startup's cloud architect reviews their monthly bill and notices costs are higher than expected for a long-running batch job. Switching from on-demand instances to Reserved Instances — or using Spot/Preemptible VMs — can reduce compute costs by up to 72 %. Questions like this test whether you understand the tradeoffs between commitment, flexibility, and cost across cloud pricing models.
What to study next
Got this wrong? Here's your next step.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
- →
Why cloud technology is transforming business — study guide chapter
Learn the concepts, then practise the questions
- →
Why cloud technology is transforming business practice questions
Targeted practice on this topic area only
- →
All GCDL questions
507 questions across all exam domains
- →
Google Cloud Digital Leader study guide
Full concept coverage aligned to exam objectives
- →
GCDL practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related GCDL practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Why cloud technology is transforming business practice questions
Practise GCDL questions linked to Why cloud technology is transforming business.
Fundamental cloud concepts practice questions
Practise GCDL questions linked to Fundamental cloud concepts.
Google Cloud products, services, and solutions practice questions
Practise GCDL questions linked to Google Cloud products, services, and solutions.
Scaling with Google Cloud operations practice questions
Practise GCDL questions linked to Scaling with Google Cloud operations.
Trust and security with Google Cloud practice questions
Practise GCDL questions linked to Trust and security with Google Cloud.
GCDL fundamentals practice questions
Practise GCDL questions linked to GCDL fundamentals.
GCDL scenario practice questions
Practise GCDL questions linked to GCDL scenario.
GCDL troubleshooting practice questions
Practise GCDL questions linked to GCDL troubleshooting.
Practice this exam
Start a free GCDL practice session
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Questions learners often ask
What does this GCDL question test?
Why cloud technology is transforming business — This question tests Why cloud technology is transforming business — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Use Database Migration Service to migrate the PostgreSQL database to Cloud SQL with continuous replication for minimal downtime. Simultaneously, rehost the application on a managed instance group with autoscaling. Have a rollback plan. — Option B is correct because it combines Database Migration Service with continuous replication (CDC) to achieve near-zero downtime for the 800 GB PostgreSQL database, while rehosting the monolithic application on a managed instance group with autoscaling to address CPU spikes without code changes. This approach respects the constraint of limited app development resources by avoiding refactoring, and the rollback plan provides safety during migration.
What should I do if I get this GCDL question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
What is the key concept behind this question?
Read the scenario before looking for a memorised answer.
About these practice questions
Courseiva creates original exam-style practice questions with explanations and wrong-answer analysis. It does not publish real exam questions, exam dumps, or protected exam content. Learn why practice questions differ from exam dumps →
Last reviewed: Jun 30, 2026
This GCDL practice question is part of Courseiva's free Google Cloud certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the GCDL exam.
Question Discussion
Share a tip, memory trick, or ask about the reasoning behind this question. Do not post real exam questions, leaked content, braindumps, or copyrighted exam material. Comments are moderated and may be removed without notice.
Sign in to join the discussion.