The answer is Elastic Load Balancing. This AWS service is the correct choice because it automatically distributes incoming application traffic across multiple EC2 instances in one or more Availability Zones, which directly improves availability and fault tolerance by rerouting requests away from any failed instance to healthy ones. On the AWS Certified Cloud Practitioner CLF-C02 exam, this concept tests your understanding of how AWS achieves high availability at the network layer; a common trap is confusing Elastic Load Balancing with Auto Scaling, but remember that ELB handles traffic distribution while Auto Scaling manages instance count. A helpful memory tip is to think of ELB as the traffic cop that keeps your application running smoothly even when individual instances go down.
CLF-C02 Cloud Technology and Services Practice Question
This CLF-C02 practice question tests your understanding of cloud technology and services. 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.
Which AWS service is used to distribute incoming application traffic across multiple EC2 instances to improve availability and fault tolerance?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Elastic Load Balancing
Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple Amazon EC2 instances in one or more Availability Zones. By doing so, it increases the fault tolerance of your application because if one instance fails, the load balancer routes traffic to the remaining healthy instances, ensuring high availability. ELB supports multiple types (Application, Network, and Gateway Load Balancers) to handle different traffic patterns and protocols.
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.
✗
Amazon Route 53
Why it's wrong here
Route 53 provides DNS routing, not direct load balancing across EC2 instances.
✗
Amazon CloudFront
Why it's wrong here
CloudFront is a CDN for content delivery, not a load balancer for EC2 instances.
✓
Elastic Load Balancing
Why this is correct
ELB distributes incoming traffic across multiple EC2 instances to improve availability and fault tolerance.
Related concept
Read the scenario before looking for a memorised answer.
✗
AWS Auto Scaling
Why it's wrong here
Auto Scaling adjusts the number of instances; ELB distributes traffic among them.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse Amazon Route 53's DNS routing policies (like weighted or latency-based routing) with actual load balancing, but Route 53 only resolves DNS queries and does not manage traffic distribution to EC2 instances at the application or network layer.
Detailed technical explanation
How to think about this question
Under the hood, Elastic Load Balancing uses a health check mechanism (e.g., HTTP/HTTPS or TCP pings) to monitor the status of each registered EC2 instance and only routes traffic to instances that pass the health check. For Application Load Balancers, traffic is distributed based on rules defined at the listener level, supporting path-based and host-based routing, which is essential for microservices architectures. In a real-world scenario, if you deploy a web application across three Availability Zones and one zone fails, ELB automatically reroutes traffic to the remaining healthy instances, maintaining application uptime without manual intervention.
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
An e-commerce site experiences heavy traffic on Black Friday and near-zero traffic during off-peak weeks. Rather than provisioning permanent large VMs, the team uses auto-scaling groups that add capacity automatically under load and reduce it overnight. Questions like this test whether you understand elasticity, availability zones, and cloud compute scaling patterns.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this CLF-C02 question in full detail.
Cloud Technology and Services — This question tests Cloud Technology and Services — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Elastic Load Balancing — Elastic Load Balancing (ELB) automatically distributes incoming application traffic across multiple Amazon EC2 instances in one or more Availability Zones. By doing so, it increases the fault tolerance of your application because if one instance fails, the load balancer routes traffic to the remaining healthy instances, ensuring high availability. ELB supports multiple types (Application, Network, and Gateway Load Balancers) to handle different traffic patterns and protocols.
What should I do if I get this CLF-C02 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 →
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.
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.
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.