The correct answer is that the file descriptor may be leaked because the close() call is skipped. This happens because when process_data(data) raises an exception, execution jumps immediately to the nearest exception handler, bypassing the f.close() statement entirely. The technical concept here is resource leak: the open file handle remains allocated in memory, consuming a system file descriptor that cannot be reused until the program ends or garbage collection intervenes. On the PCAP exam, this scenario tests your understanding of file I/O exception handling and the dangers of manual resource management—a common trap is assuming close() will always run, when in fact any unhandled exception breaks that flow. The examiners want you to recognize that Python’s with statement is the safe alternative, as it guarantees cleanup via context manager protocols. Memory tip: think of a try block without a finally as a door left open—if an exception crashes the party, nobody shuts the door behind them.
PCAP Exceptions and File I/O Practice Question
This PCAP practice question tests your understanding of exceptions and file i/o. Read the scenario carefully and evaluate each option against the stated constraints before committing to an answer. 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.
Consider the code fragment:
f = open('data.txt', 'r')
data = f.read()
process_data(data)
f.close()
What is the primary risk if an exception occurs during process_data(data)?
Clue words in this question
Noticing these words before you look at the options changes how you read each choice.
Clue: "primary"
Why it matters: Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
The file descriptor may be leaked because the close() call is skipped.
Option A is correct because if `process_data(data)` raises an exception, the `f.close()` statement is never executed, leaving the file descriptor open. This is a resource leak that can exhaust system file handles, especially in long-running applications. Python's `with` statement is the recommended approach to guarantee automatic cleanup even when exceptions occur.
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 file descriptor may be leaked because the close() call is skipped.
Why this is correct
Correct: if an exception occurs, close() is not called.
Clue confirmation
The clue word "primary" in the question point toward this answer.
Related concept
Read the scenario before looking for a memorised answer.
✗
The exception will be silently suppressed.
Why it's wrong here
Exception propagates normally unless caught.
✗
The file will be automatically closed by Python's garbage collector immediately.
Why it's wrong here
GC may close file eventually, but not immediately and not guaranteed.
✗
The file contents will be corrupted.
Why it's wrong here
No corruption; file remains open but not corrupted.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Python Institute often tests the misconception that Python's garbage collector immediately closes files, when in reality it only closes them during an unpredictable collection cycle, making explicit cleanup essential.
Detailed technical explanation
How to think about this question
File descriptors are a finite OS resource; on Linux, the default per-process limit is often 1024. Without explicit closure (or a `with` block that calls `__exit__`), the file remains open until the process terminates or the garbage collector runs, which is non-deterministic. The `with` statement uses a context manager that guarantees `f.close()` is called even if an exception occurs, making it the idiomatic Python pattern for file I/O.
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 cloud solutions architect for a retail company is evaluating services for a new workload. The correct answer here reflects best practice for the specific scenario described — not a general cloud recommendation. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Cloud exam questions reward reading the constraint carefully: the same technology can be right or wrong depending on the use case.
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.
Exceptions and File I/O — This question tests Exceptions and File I/O — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: The file descriptor may be leaked because the close() call is skipped. — Option A is correct because if `process_data(data)` raises an exception, the `f.close()` statement is never executed, leaving the file descriptor open. This is a resource leak that can exhaust system file handles, especially in long-running applications. Python's `with` statement is the recommended approach to guarantee automatic cleanup even when exceptions occur.
What should I do if I get this PCAP 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: "primary". Asks for the main purpose or function, not a secondary benefit. Eliminate answers that describe side-effects or partial functions.
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 →
These questions test the same concept from different angles. Work through them to make sure you can recognise it however the exam phrases it.
Variation 1. A Python script processes a log file line by line. If a line cannot be decoded due to an encoding error, the script should skip the line and continue. Which exception handling approach is best?
medium
A.Wrap the entire file reading in a try-except block without specifying exception type.
B.Use a try-except-else block to handle success and failure separately, exiting on failure.
✓ C.Inside the loop, wrap the line decoding in a try-except UnicodeDecodeError block and continue.
D.Catch Exception in the outer loop and break on error.
Why C: Option C is correct because it places the try-except block inside the loop, specifically catching `UnicodeDecodeError` for each line. This allows the script to skip only the problematic line and continue processing subsequent lines, which matches the requirement exactly.
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This PCAP practice question is part of Courseiva's free Python Institute 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 PCAP exam.
Question Discussion
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