- A
Azure SQL Database with active geo-replication
Why wrong: Active geo-replication provides disaster recovery and read-only replicas, but it does not support multi-region writes with single-digit millisecond latencies for global distribution.
- B
Azure Cosmos DB with multi-region writes
Cosmos DB natively supports globally distributed data with multi-region writes, automatic and synchronous replication, and guaranteed single-digit millisecond latency at the 99th percentile for reads and writes. It also handles JSON documents with variable schemas.
- C
Azure Table Storage
Why wrong: Azure Table Storage is a NoSQL key-value store that does not provide multi-region writes with low latency or native JSON document support.
- D
Azure Database for PostgreSQL with read replicas
Why wrong: Azure Database for PostgreSQL with read replicas supports read scaling across regions but not multi-region writes with single-digit millisecond latencies.
AZ-305 Design data storage solutions Practice Question
This AZ-305 practice question tests your understanding of design data storage solutions. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 company runs a global e-commerce application that needs to store product catalog data. The data is JSON documents with variable schemas. The application requires single-digit millisecond read and write latencies at any scale and must support automatic synchronous replication across multiple Azure regions for high availability and low latency reads from any region. Which Azure data service should they choose?
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
Azure Cosmos DB with multi-region writes
Azure Cosmos DB with multi-region writes is the correct choice because it natively supports JSON documents with variable schemas, guarantees single-digit millisecond read and write latencies at any scale via its multi-homing API, and provides automatic synchronous replication across multiple Azure regions with active-active configurations. This ensures high availability and low-latency reads from any region without manual failover or data loss.
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.
- ✗
Azure SQL Database with active geo-replication
Why it's wrong here
Active geo-replication provides disaster recovery and read-only replicas, but it does not support multi-region writes with single-digit millisecond latencies for global distribution.
- ✓
Azure Cosmos DB with multi-region writes
Why this is correct
Cosmos DB natively supports globally distributed data with multi-region writes, automatic and synchronous replication, and guaranteed single-digit millisecond latency at the 99th percentile for reads and writes. It also handles JSON documents with variable schemas.
Related concept
Read the scenario before looking for a memorised answer.
- ✗
Azure Table Storage
Why it's wrong here
Azure Table Storage is a NoSQL key-value store that does not provide multi-region writes with low latency or native JSON document support.
- ✗
Azure Database for PostgreSQL with read replicas
Why it's wrong here
Azure Database for PostgreSQL with read replicas supports read scaling across regions but not multi-region writes with single-digit millisecond latencies.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse 'automatic synchronous replication' with 'active geo-replication' or 'read replicas,' assuming that any multi-region database service provides synchronous writes, whereas only Cosmos DB with multi-region writes offers true synchronous replication across regions for both reads and writes.
Detailed technical explanation
How to think about this question
Cosmos DB achieves single-digit millisecond latencies through its use of a write-optimized B-tree index and a multi-master replication protocol based on a quorum-committed log, which synchronously replicates writes to all configured regions before acknowledging the client. The multi-region writes feature leverages the Azure Cosmos DB Gateway to route requests to the nearest write region, and conflict resolution policies (e.g., last-writer-wins or custom) handle concurrent updates across regions, ensuring eventual consistency with strong consistency options available for single-region writes.
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 media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
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.
- →
Design data storage solutions — study guide chapter
Learn the concepts, then practise the questions
- →
Design data storage solutions practice questions
Targeted practice on this topic area only
- →
All AZ-305 questions
999 questions across all exam domains
- →
Microsoft Azure Solutions Architect Expert AZ-305 study guide
Full concept coverage aligned to exam objectives
- →
AZ-305 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related AZ-305 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Design identity, governance, and monitoring solutions practice questions
Practise AZ-305 questions linked to Design identity, governance, and monitoring solutions.
Design data storage solutions practice questions
Practise AZ-305 questions linked to Design data storage solutions.
Design business continuity solutions practice questions
Practise AZ-305 questions linked to Design business continuity solutions.
Design infrastructure solutions practice questions
Practise AZ-305 questions linked to Design infrastructure solutions.
SAA-C03 VPC practice questions
Practise AZ-305 questions linked to SAA-C03 VPC.
SAA-C03 S3 lifecycle policy questions
Practise AZ-305 questions linked to SAA-C03 S3 lifecycle policy questions.
SAA-C03 RDS Multi-AZ questions
Practise AZ-305 questions linked to SAA-C03 RDS Multi-AZ questions.
SAA-C03 IAM policy practice questions
Practise AZ-305 questions linked to SAA-C03 IAM policy.
SAA-C03 Route 53 failover questions
Practise AZ-305 questions linked to SAA-C03 Route 53 failover questions.
SAA-C03 CloudFront practice questions
Practise AZ-305 questions linked to SAA-C03 CloudFront.
SAA-C03 NAT gateway questions
Practise AZ-305 questions linked to SAA-C03 NAT gateway questions.
SAA-C03 VPC endpoint questions
Practise AZ-305 questions linked to SAA-C03 VPC endpoint questions.
Practice this exam
Start a free AZ-305 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 AZ-305 question test?
Design data storage solutions — This question tests Design data storage solutions — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Azure Cosmos DB with multi-region writes — Azure Cosmos DB with multi-region writes is the correct choice because it natively supports JSON documents with variable schemas, guarantees single-digit millisecond read and write latencies at any scale via its multi-homing API, and provides automatic synchronous replication across multiple Azure regions with active-active configurations. This ensures high availability and low-latency reads from any region without manual failover or data loss.
What should I do if I get this AZ-305 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 11, 2026
This AZ-305 practice question is part of Courseiva's free Microsoft 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 AZ-305 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.