CLF-C02 Cloud Concepts Practice Question

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

• ✗

  Scalability

  Why it's wrong here

  Scalability is the ability of a system to handle increased load by adding more computing capacity, either by resizing instances (vertical scaling) or adding more instances (horizontal scaling). It addresses growth in demand, but a single Availability Zone deployment still has a fault domain limitation: if that zone fails, all scaled resources fail with it. Scalability does not imply resilience—the system may be able to serve a million users, but it remains vulnerable to the loss of its underlying infrastructure.

  When this WOULD be correct

  A question asking: 'A company expects a sudden spike in traffic during a flash sale. Which AWS concept allows the application to automatically add EC2 instances to handle the load?' would make scalability the correct answer.

• ✓

  High availability

  Why this is correct

  High availability is the ability of a system to continue functioning automatically when a component fails, such as an entire Availability Zone. In AWS, this is achieved by deploying redundant resources across multiple Availability Zones, using services like Elastic Load Balancing and Auto Recovery, and implementing health checks that automatically reroute traffic to healthy instances. For a critical e-commerce application, designing for high availability means eliminating single points of failure so that an AZ outage does not interrupt customer transactions and no manual intervention is needed.

• ✗

  Elasticity

  Why it's wrong here

  Elasticity is the capacity to automatically adjust computing resources to match fluctuating demand, for example using EC2 Auto Scaling to add instances during peak load and remove them afterward. Although elasticity can help absorb traffic spikes, it reacts to metrics like CPU utilization, not to infrastructure failures, so it cannot restore or reroute workloads if an Availability Zone goes down. All resources within the failed zone remain unavailable regardless of how many instances are running, meaning elasticity provides no inherent protection against zone outages.

  When this WOULD be correct

  A question asking which AWS concept allows an application to automatically add EC2 instances during traffic spikes and remove them during low traffic, without manual intervention.

• ✗

  Disaster recovery

  Why it's wrong here

  Disaster recovery is a separate discipline focused on restoring systems after a catastrophic event, such as a regional outage or data corruption, using backups, snapshots, or failover to a different region. While important, DR typically involves defined Recovery Point and Recovery Time objectives, often requiring some downtime and manual steps to promote backups or re-provision infrastructure. The stated requirement stresses continued operation without manual intervention, which goes beyond DR's recovery-oriented model—DR restores service after the fact rather than preventing loss of availability.

  When this WOULD be correct

  A question asks: 'A company needs to restore a critical application after a regional outage with a recovery time objective of 4 hours. Which concept describes this requirement?' Disaster recovery would be correct because it focuses on recovery after a disaster with defined RTO/RPO.

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.

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?”