PCD Building and testing applications Practice Question
This PCD practice question tests your understanding of building and testing applications. 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.
Exhibit
Refer to the exhibit.
{
"bindings": [
{
"role": "roles/cloudbuild.builds.builder",
"members": [
"serviceAccount:build-sa@my-project.iam.gserviceaccount.com"
]
}
]
}
Refer to the exhibit. A developer is configuring Cloud Build to build a Docker image from a Cloud Source Repository. The build fails with a permission error. What is the most likely reason?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "most likely"
Why it matters: Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The service account is missing the roles/source.reader role to access the repository
The build fails with a permission error because the Cloud Build service account does not have the `roles/source.reader` role on the Cloud Source Repository. Without this role, the service account cannot read the source code from the repository, which is required to trigger the build. The error is not about building permissions but about accessing the source.
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.
✗
The service account lacks the roles/cloudbuild.builds.builder role
Why it's wrong here
It already has that role as shown in the exhibit.
✓
The service account is missing the roles/source.reader role to access the repository
Why this is correct
Cloud Build needs source.reader to read the repository.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
The Cloud Source Repository does not have the build trigger enabled
Why it's wrong here
The trigger is separate; the error is during build, not trigger.
✗
The build config file is missing the 'source' field
Why it's wrong here
The error is about permissions, not configuration.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Cisco often tests the distinction between build execution permissions (roles/cloudbuild.builds.builder) and source access permissions (roles/source.reader), leading candidates to incorrectly choose the builder role when the actual error is about reading the source repository.
Trap categories for this question
Command / output trap
It already has that role as shown in the exhibit.
Detailed technical explanation
How to think about this question
Cloud Build uses a default service account (e.g., `[PROJECT_NUMBER]@cloudbuild.gserviceaccount.com`) to access resources. For Cloud Source Repository, the service account must have the `roles/source.reader` IAM role, which grants `source.repos.get` and `source.repos.list` permissions. Without this, the build fails at the source retrieval stage, even if the build config and Dockerfile are correct. In real-world scenarios, this often occurs when a project uses a custom service account that lacks the necessary source repository permissions.
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
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.
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Building and testing applications — This question tests Building and testing applications — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The service account is missing the roles/source.reader role to access the repository — The build fails with a permission error because the Cloud Build service account does not have the `roles/source.reader` role on the Cloud Source Repository. Without this role, the service account cannot read the source code from the repository, which is required to trigger the build. The error is not about building permissions but about accessing the source.
What should I do if I get this PCD question wrong?
Identify which exam domain this question belongs to, review the core concept, then practise similar questions from the same domain.
Are there clue words in this question I should notice?
Yes — watch for: "most likely". Probability qualifier — the question wants the most probable cause or outcome, not a guaranteed one. Eliminate low-probability options.
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 PCD practice question is part of Courseiva's free Google Cloud 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 PCD 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.