hardMultiple ChoiceObjective-mapped
FC0-U71 A developer sees the above output Practice Question
Network Topology
A developer sees the above output. After a recent commit, the application crashed due to a null pointer. Which commit likely introduced the null pointer issue?
⚠ Common exam trap
CompTIA often tests the concept of causality in version control by presenting a chronological list of commits and asking which one introduced a bug, and the trap here is that candidates might assume the bug was introduced by the most recent commit overall (012jkl) rather than the commit immediately preceding the crash.
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
✓
def456
The commit def456 is the most recent commit before the crash, and since the null pointer exception occurred after this commit, it is the most likely source of the bug. In version control systems like Git, a null pointer error typically indicates that a recent code change introduced a reference to an object that was not properly initialized. The developer should inspect the changes in def456 for uninitialized variables or missing null checks.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
def456
Why this is correct
The null pointer bug likely originated in the new feature commit def456.
- ✗
abc123
Why it's wrong here
abc123 is a later fix, not the introducer.
- ✗
012jkl
Why it's wrong here
Initial commit likely did not contain the bug.
- ✗
789ghi
Why it's wrong here
789ghi is the fix commit.
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JA
Written by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
This FC0-U71 practice question is part of Courseiva's free CompTIA 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 FC0-U71 exam.