- A
Condition: { "Null": { "aws:MultiFactorAuthPresent": "false" } }
This denies access if the MFA key is absent (null), effectively requiring MFA.
- B
Condition: { "StringLike": { "iam:MFADeviceType": "Virtual" } }
Why wrong: This checks the type of MFA device, not whether MFA was used.
- C
Condition: { "ForAllValues:StringEquals": { "aws:SourceIdentity": "admin" } }
Why wrong: This checks the source identity, not MFA.
- D
Condition: { "StringEquals": { "iam:ResourcePath": "/" } }
Why wrong: This condition checks the resource path, not MFA status.
- E
Condition: { "Bool": { "aws:MultiFactorAuthPresent": "true" } }
This condition ensures that MFA was used during the request.
Question 1,020 of 1,616
IAM Policy Conditions for MFA Enforcement
This DVA-C02 practice question tests your understanding of development with aws services. 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. A key principle to apply: null Condition Operator. 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 TWO IAM policy conditions can be used to enforce multi-factor authentication (MFA) for API calls?
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
✓
Condition: { "Null": { "aws:MultiFactorAuthPresent": "false" } }
Option A is correct because the `Null` condition operator checks whether the `aws:MultiFactorAuthPresent` key is absent or explicitly set to `false`. When set to `false`, it denies API calls that were made without MFA, effectively enforcing MFA for all API operations. Option E is correct because the `Bool` condition operator with `true` requires that MFA was used, but it must be combined with a `Deny` effect to block unauthenticated requests; used alone in an `Allow` statement, it only permits MFA-authenticated calls without blocking non-MFA ones.
Key principle: Null Condition Operator
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
Condition: { "Null": { "aws:MultiFactorAuthPresent": "false" } }
Why this is correct
This denies access if the MFA key is absent (null), effectively requiring MFA.
Related concept
Null Condition Operator
- ✗
Condition: { "StringLike": { "iam:MFADeviceType": "Virtual" } }
Why it's wrong here
This checks the type of MFA device, not whether MFA was used.
- ✗
Condition: { "ForAllValues:StringEquals": { "aws:SourceIdentity": "admin" } }
Why it's wrong here
This checks the source identity, not MFA.
- ✗
Condition: { "StringEquals": { "iam:ResourcePath": "/" } }
Why it's wrong here
This condition checks the resource path, not MFA status.
- ✓
Condition: { "Bool": { "aws:MultiFactorAuthPresent": "true" } }
Why this is correct
This condition ensures that MFA was used during the request.
Related concept
Null Condition Operator
Common exam traps
Common exam trap: answer the scenario, not the keyword
A common trap is thinking that using the Bool condition with true alone (e.g., "Bool": { "aws:MultiFactorAuthPresent": "true" }) is sufficient to enforce MFA. However, without a Deny effect or a Null check, this only allows MFA-authenticated calls but does not block non-MFA calls, leaving a security gap.
Detailed technical explanation
How to think about this question
The `aws:MultiFactorAuthPresent` key is a boolean that is `true` only when the caller authenticated with a temporary credential (e.g., from STS AssumeRole) that required MFA, or when using IAM user credentials with an MFA device. A common subtlety is that long-term access keys (e.g., root user or IAM user without MFA) will have this key set to `false` or absent, which is why the `Null` operator is often used to catch both cases. In real-world scenarios, you might combine this condition with `aws:SourceIp` to allow MFA-less access from trusted networks while requiring MFA from external IPs.
KKey Concepts to Remember
- Null Condition Operator
- Bool Condition Operator
- aws:MultiFactorAuthPresent
- IAM Policy Conditions for MFA
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
Null Condition Operator
Real-world example
How this comes up in practice
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
Got this wrong? Here's your next step.
Review null Condition Operator, then practise related DVA-C02 questions on the same topic to reinforce the concept.
- →
Development with AWS Services — study guide chapter
Learn the concepts, then practise the questions
- →
Development with AWS Services practice questions
Targeted practice on this topic area only
- →
All DVA-C02 questions
1,616 questions across all exam domains
- →
AWS Certified Developer Associate DVA-C02 study guide
Full concept coverage aligned to exam objectives
- →
DVA-C02 practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related DVA-C02 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Development with AWS Services practice questions
Practise DVA-C02 questions linked to Development with AWS Services.
Security practice questions
Practise DVA-C02 questions linked to Security.
Deployment practice questions
Practise DVA-C02 questions linked to Deployment.
Troubleshooting and Optimization practice questions
Practise DVA-C02 questions linked to Troubleshooting and Optimization.
DVA-C02 fundamentals practice questions
Practise DVA-C02 questions linked to DVA-C02 fundamentals.
DVA-C02 scenario practice questions
Practise DVA-C02 questions linked to DVA-C02 scenario.
DVA-C02 troubleshooting practice questions
Practise DVA-C02 questions linked to DVA-C02 troubleshooting.
Practice this exam
Start a free DVA-C02 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 DVA-C02 question test?
Development with AWS Services — This question tests Development with AWS Services — Null Condition Operator.
What is the correct answer to this question?
The correct answer is: Condition: { "Null": { "aws:MultiFactorAuthPresent": "false" } } — Option A is correct because the `Null` condition operator checks whether the `aws:MultiFactorAuthPresent` key is absent or explicitly set to `false`. When set to `false`, it denies API calls that were made without MFA, effectively enforcing MFA for all API operations. Option E is correct because the `Bool` condition operator with `true` requires that MFA was used, but it must be combined with a `Deny` effect to block unauthenticated requests; used alone in an `Allow` statement, it only permits MFA-authenticated calls without blocking non-MFA ones.
What should I do if I get this DVA-C02 question wrong?
Review null Condition Operator, then practise related DVA-C02 questions on the same topic to reinforce the concept.
What is the key concept behind this question?
Null Condition Operator
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
More DVA-C02 practice questions
- A developer is troubleshooting an AWS Lambda function that is triggered by an S3 event. The function occasionally fails…
- A developer needs to call AWS APIs from application code running on EC2. Which credential source should the AWS SDK use…
- A developer needs to allow an IAM user in a different AWS account to assume a role in the developer's account. The role…
- A developer needs to grant an IAM role in Account B read-only access to objects in an S3 bucket in Account A. The bucket…
- An API Gateway HTTP API should allow access only to users authenticated by an external OIDC provider. Which authorizer t…
- A developer needs to allow an EC2 instance to read from a DynamoDB table. Which is the best practice to grant permission…
Last reviewed: Jul 4, 2026
This DVA-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 DVA-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.