- A
The VPC has a default route to the internet via NAT.
Why wrong: A default route would cause traffic to go internet, but Private Google Access overrides that if enabled.
- B
The DNS record for bigquery.googleapis.com points to the public IP.
Why wrong: DNS should be configured to point to the PSC endpoint IP, but if Private Google Access is off, VMs ignore it.
- C
Private Google Access is disabled on the subnet.
Private Google Access must be enabled for VMs to use the PSC endpoint for Google APIs.
- D
The PSC endpoint is not associated with a forwarding rule.
Why wrong: The endpoint is associated with a forwarding rule automatically when created.
Question 988 of 985
PCSE Configuring Network Security Practice Question
This PCSE practice question tests your understanding of configuring network security. This is a configuration task: choose the command set that satisfies every stated requirement. Small differences — like 'secret' vs 'password' or 'transport input ssh' vs 'all' — change whether the answer is correct. 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 financial services company must ensure that all data egress from a VPC to BigQuery goes through a Private Service Connect endpoint for private access. They have set up the PSC endpoint and configured DNS. However, connections from VMs are still using the public internet. What is the most likely cause?
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 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
✓
Private Google Access is disabled on the subnet.
For private access to Google APIs via PSC, the VPC must have Private Google Access enabled on the subnet. Without it, VMs will use the default public route.
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
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
The VPC has a default route to the internet via NAT.
Why it's wrong here
A default route would cause traffic to go internet, but Private Google Access overrides that if enabled.
- ✗
The DNS record for bigquery.googleapis.com points to the public IP.
Why it's wrong here
DNS should be configured to point to the PSC endpoint IP, but if Private Google Access is off, VMs ignore it.
- ✓
Private Google Access is disabled on the subnet.
Why this is correct
Private Google Access must be enabled for VMs to use the PSC endpoint for Google APIs.
Clue confirmation
The clue word "most likely" in the question point toward this answer.
Related concept
CIDR notation defines the prefix length.
- ✗
The PSC endpoint is not associated with a forwarding rule.
Why it's wrong here
The endpoint is associated with a forwarding rule automatically when created.
Common exam traps
Common exam trap: usable hosts are not the same as total addresses
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
How to think about this question
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.
KKey Concepts to Remember
- CIDR notation defines the prefix length.
- Block size helps identify subnet boundaries.
- Network and broadcast addresses are not usable hosts in normal IPv4 subnets.
- The required host count determines the smallest suitable subnet.
TExam Day Tips
- Write the block size before choosing the subnet.
- Check whether the question asks for hosts, subnets or a specific address range.
- Do not confuse /24, /25, /26 and /27 host counts.
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
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.
Visual reference
What to study next
Got this wrong? Here's your next step.
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related PCSE subnetting questions on CIDR, address ranges, and subnet selection.
- →
Configuring Network Security — study guide chapter
Learn the concepts, then practise the questions
- →
Configuring Network Security practice questions
Targeted practice on this topic area only
- →
All PCSE questions
985 questions across all exam domains
- →
Google Professional Cloud Security Engineer study guide
Full concept coverage aligned to exam objectives
- →
PCSE practice test guide
How to use practice tests most effectively before exam day
Related practice questions
Related PCSE practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
Configuring Access Within a Cloud Solution Environment practice questions
Practise PCSE questions linked to Configuring Access Within a Cloud Solution Environment.
Ensuring Data Protection practice questions
Practise PCSE questions linked to Ensuring Data Protection.
Managing Operations in a Cloud Solution Environment practice questions
Practise PCSE questions linked to Managing Operations in a Cloud Solution Environment.
Configuring Network Security practice questions
Practise PCSE questions linked to Configuring Network Security.
Supporting Compliance Requirements practice questions
Practise PCSE questions linked to Supporting Compliance Requirements.
PCSE fundamentals practice questions
Practise PCSE questions linked to PCSE fundamentals.
PCSE scenario practice questions
Practise PCSE questions linked to PCSE scenario.
PCSE troubleshooting practice questions
Practise PCSE questions linked to PCSE troubleshooting.
Practice this exam
Start a free PCSE 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 PCSE question test?
Configuring Network Security — This question tests Configuring Network Security — CIDR notation defines the prefix length..
What is the correct answer to this question?
The correct answer is: Private Google Access is disabled on the subnet. — For private access to Google APIs via PSC, the VPC must have Private Google Access enabled on the subnet. Without it, VMs will use the default public route.
What should I do if I get this PCSE question wrong?
Review block sizes, usable host formulas (2^n − 2), and how to find network and broadcast addresses for /24 through /30. Then practise related PCSE subnetting questions on CIDR, address ranges, and subnet selection.
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?
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 →
Last reviewed: Jul 4, 2026
This PCSE 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 PCSE 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.