Quick Answer
The correct answer is the Application Load Balancer. AWS WAF must be associated directly with the ALB because it operates at Layer 7, inspecting HTTP/HTTPS requests before they reach the load balancer, which allows it to filter out SQL injection attacks at the application layer. On the AWS Certified Advanced Networking Specialty ANS-C01 exam, this question tests your understanding of where WAF web ACLs can be attached—specifically, they integrate with ALBs, CloudFront distributions, and API Gateways, but not with Route 53, internet gateways, or security groups. A common trap is assuming WAF can protect network-level components like an internet gateway, but WAF is purely an application-layer firewall. Remember the memory tip: "WAF works at Layer 7, so it needs a Layer 7 endpoint like an ALB, not a network device."
This ANS-C01 practice question tests your understanding of network implementation. Match the stated requirement to the specific cloud service, access model, or configuration option — many options are valid in isolation but not for this scenario. 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 has deployed an application in a VPC with public and private subnets across two Availability Zones. The application uses an Application Load Balancer (ALB) in the public subnets to distribute traffic to EC2 instances in the private subnets. The company wants to use AWS WAF to protect against SQL injection attacks. Where should the AWS WAF web ACL be associated?
The Application Load Balancer.
AWS WAF can be associated with an ALB for web traffic protection.
Amazon Route 53 hosted zone.
Why wrong: Route 53 does not support direct association with AWS WAF.
The security group of the EC2 instances.
Why wrong: Security groups are stateful firewalls but do not integrate with AWS WAF.
The VPC internet gateway.
Why wrong: Internet gateways do not support AWS WAF association.
Answer choices
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
The Application Load Balancer.
Option B is correct because AWS WAF can be associated with an ALB. Option A is wrong because AWS WAF does not directly protect Route 53. Option C is wrong because AWS WAF does not protect an internet gateway. Option D is wrong because AWS WAF is not associated with security groups.
Key principle: Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Answer analysis
For each option: why learners choose it and why it is or isn't the right answer here.
The Application Load Balancer.
Why this is correct
AWS WAF can be associated with an ALB for web traffic protection.
Related concept
CIDR notation defines the prefix length.
Amazon Route 53 hosted zone.
Why it's wrong here
Route 53 does not support direct association with AWS WAF.
The security group of the EC2 instances.
Why it's wrong here
Security groups are stateful firewalls but do not integrate with AWS WAF.
The VPC internet gateway.
Why it's wrong here
Internet gateways do not support AWS WAF association.
Common exam traps
Subnetting questions often tempt you into counting all addresses. In normal IPv4 subnets, the network and broadcast addresses are not usable host addresses.
Detailed technical explanation
Subnetting questions test whether you can identify the network, broadcast address, usable range, mask and correct subnet. Slow down enough to calculate the block size correctly.
Key takeaway
Count usable hosts — not total addresses — and remember that the network and broadcast addresses are not available to hosts in standard IPv4 subnets.
Real-world example
A company's IT admin needs to give a contractor read-only access to production logs without sharing account credentials. Using role-based access control (RBAC) and temporary scoped permissions — not a permanent shared password — is the correct pattern. Questions like this test whether you can apply least-privilege access across cloud identity services.
What to study next
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related ANS-C01 subnetting questions on CIDR, address ranges, and subnet selection.
Network Implementation — study guide chapter
Learn the concepts, then practise the questions
Network Implementation practice questions
Targeted practice on this topic area only
All ANS-C01 questions
1,705 questions across all exam domains
AWS Certified Advanced Networking Specialty ANS-C01 study guide
Full concept coverage aligned to exam objectives
ANS-C01 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Practise ANS-C01 questions linked to Network Management and Operations.
Practise ANS-C01 questions linked to Network Security, Compliance and Governance.
Practise ANS-C01 questions linked to Network Design.
Practise ANS-C01 questions linked to Network Implementation.
Practise ANS-C01 questions linked to ANS-C01 fundamentals.
Practise ANS-C01 questions linked to ANS-C01 scenario.
Practise ANS-C01 questions linked to ANS-C01 troubleshooting.
Practice this exam
Short sessions build daily habit. Longer sessions build exam-day stamina. Try a timed session to simulate real conditions.
FAQ
Network Implementation — This question tests Network Implementation — CIDR notation defines the prefix length..
The correct answer is: The Application Load Balancer. — Option B is correct because AWS WAF can be associated with an ALB. Option A is wrong because AWS WAF does not directly protect Route 53. Option C is wrong because AWS WAF does not protect an internet gateway. Option D is wrong because AWS WAF is not associated with security groups.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related ANS-C01 subnetting questions on CIDR, address ranges, and subnet selection.
CIDR notation defines the prefix length.
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 →
Keep practising
Last reviewed: Jun 20, 2026
This ANS-C01 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 ANS-C01 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.