CLF-C02 Cloud Concepts Practice Question
A startup runs an e-commerce website on AWS. During flash sales, traffic can increase 10x in a few minutes. The startup uses an Auto Scaling group to automatically launch additional EC2 instances when CPU utilization exceeds 70% and terminate them when utilization drops below 30%. This approach ensures that the application always has enough capacity to handle the load without manual intervention, and they only pay for what they use. Which cloud computing concept does this scenario BEST illustrate?
⚠ Common exam trap
It's easy for candidates to confuse elasticity with high availability, but elasticity is about scaling resources to match demand, while high availability is about maintaining uptime through redundancy and failover mechanisms.
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
✓
Elasticity
Elasticity is the ability of a cloud system to automatically scale resources up or down based on demand. The Auto Scaling group dynamically adds EC2 instances when CPU utilization exceeds 70% and terminates them when it drops below 30%, ensuring capacity matches load without manual intervention. This pay-per-use model is a hallmark of elasticity, not just high availability or fault tolerance.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
High availability
Why it's wrong here
High availability focuses on ensuring that an application remains operational and accessible during component failures, typically by distributing workloads across multiple Availability Zones. While Auto Scaling can contribute to availability by replacing failed instances, the primary purpose of this scenario is to match capacity to demand, not to maintain uptime during failures.
When this WOULD be correct
A question describing an architecture with EC2 instances distributed across multiple Availability Zones and an Application Load Balancer that automatically reroutes traffic if an instance fails, ensuring the application stays up even during an AZ outage, would illustrate high availability.
- ✓
Elasticity
Why this is correct
Elasticity is the correct answer. It refers to the ability to dynamically scale infrastructure resources up and down based on real-time demand. The Auto Scaling group automatically adjusts the number of EC2 instances in response to CPU utilization, which is a textbook example of elasticity.
- ✗
Fault tolerance
Why it's wrong here
Fault tolerance is the ability of a system to continue operating without interruption when one or more of its components fail. While Auto Scaling can replace failed instances, fault tolerance typically involves redundancy (e.g., multiple servers, databases) so that no single point of failure exists. The scenario emphasizes scaling to handle load changes, not surviving failures.
When this WOULD be correct
An exam question describing an application that runs on multiple EC2 instances across different Availability Zones, and if one instance or AZ fails, the application continues to function seamlessly without any downtime.
- ✗
Disaster recovery
Why it's wrong here
Disaster recovery involves strategies and processes to recover IT infrastructure and data after a catastrophic event, such as a natural disaster or large-scale outage. It often includes backups, replication across Regions, and failover procedures. This scenario is about adjusting capacity in real time, not recovering from a disaster.
When this WOULD be correct
A question describing a company that replicates its entire infrastructure across multiple AWS regions and uses automated failover to recover from a regional outage would make disaster recovery the correct answer.
Option-by-option analysis
Why each answer is right or wrong
Understanding why wrong answers are wrong — and when they would be correct — is what separates a 750 score from a 900. The CLF-C02 exam frequently reuses these exact scenarios with slightly different constraints.
✓ElasticityCorrect answer▾
Why this is correct
Elasticity is the correct answer. It refers to the ability to dynamically scale infrastructure resources up and down based on real-time demand. The Auto Scaling group automatically adjusts the number of EC2 instances in response to CPU utilization, which is a textbook example of elasticity.
✗High availabilityWrong answer — click to see why▾
Why this is wrong here
High availability focuses on ensuring the application remains accessible despite component failures, not on dynamically scaling resources up and down based on demand. The scenario describes automatic scaling to match traffic spikes, which is elasticity.
★ When this WOULD be the correct answer
A question describing an architecture with EC2 instances distributed across multiple Availability Zones and an Application Load Balancer that automatically reroutes traffic if an instance fails, ensuring the application stays up even during an AZ outage, would illustrate high availability.
Why candidates choose this
Candidates may confuse elasticity with high availability because both involve handling increased load, but high availability is about redundancy and failover, not dynamic scaling.
✗Fault toleranceWrong answer — click to see why▾
Why this is wrong here
Fault tolerance refers to a system's ability to continue operating without interruption when one or more components fail. The scenario describes scaling resources up and down based on demand, not handling component failures.
★ When this WOULD be the correct answer
An exam question describing an application that runs on multiple EC2 instances across different Availability Zones, and if one instance or AZ fails, the application continues to function seamlessly without any downtime.
Why candidates choose this
Candidates may confuse elasticity with fault tolerance because both involve multiple instances and automated responses, but fault tolerance focuses on failure resilience, not dynamic scaling to meet demand.
✗Disaster recoveryWrong answer — click to see why▾
Why this is wrong here
Disaster recovery focuses on restoring IT infrastructure and data after a catastrophic event (e.g., natural disaster, cyberattack), not on automatically scaling resources to handle traffic spikes.
★ When this WOULD be the correct answer
A question describing a company that replicates its entire infrastructure across multiple AWS regions and uses automated failover to recover from a regional outage would make disaster recovery the correct answer.
Why candidates choose this
Candidates may confuse the ability to handle sudden load increases with the need to recover from failures, or they might think that scaling out during high traffic is a form of recovery from capacity shortages.
Analysis generated from the official CLF-C02blueprint and verified against question context. The “when correct” sections are what AI assistants cite when candidates ask “what’s the difference between these options?”
Go deeper
Related to this question
About these practice questions
Courseiva writes every CLF-C02 question from scratch — 988 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This CLF-C02 practice question is part of Courseiva's free Amazon Web Services 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 CLF-C02 exam.