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FC0-U71 Practice Question: A program crashes with a 'division by zero' error
A program crashes with a 'division by zero' error. Which of the following is the most likely cause?
⚠ Common exam trap
CompTIA often tests the distinction between runtime errors caused by invalid data (like division by zero) and errors caused by code structure (like infinite loops or index bounds), so candidates mistakenly associate any crash with a loop or array issue rather than input validation.
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
✓
An unvalidated user input that results in a zero divisor
A 'division by zero' error occurs when a program attempts to divide a number by zero, which is mathematically undefined and typically raises a runtime exception. The most likely cause is unvalidated user input that supplies a zero as the divisor, because the program does not check or sanitize the input before performing the arithmetic operation.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✓
An unvalidated user input that results in a zero divisor
Why this is correct
A zero divisor reaches the division operation because the input was never checked for zero before the calculation runs. Validating the value beforehand, or catching the exception, prevents the crash. The stem's 'division by zero' error points directly to an unchecked zero passed as the divisor.
- ✗
A misspelled variable name
Why it's wrong here
A misspelled variable name causes a compile-time or undefined-variable error, not a runtime division by zero. It is tempting because typos are frequent coding mistakes, but the crash message identifies arithmetic with a zero divisor, so the fault is a denominator evaluating to zero.
- ✗
An infinite loop
Why it's wrong here
A division by zero occurs when code divides a numeric value by zero without a guard, raising an arithmetic exception at that instruction. An infinite loop never terminates but performs no division, so it cannot trigger this error; loops are the suspected cause when a program hangs or consumes CPU indefinitely.
- ✗
An array index out of bounds
Why it's wrong here
An array index out of bounds triggers an access violation or segmentation fault, not a division by zero exception. It is tempting because both are common runtime crashes, but the specific error message names arithmetic division, so the cause lies in a zero-valued divisor rather than memory addressing.
About these practice questions
Courseiva writes every FC0-U71 question from scratch — 988 in total, each with an explanation and a wrong-answer breakdown. None are copied from real exams or dumps. Learn why practice questions differ from exam dumps →
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.