PCAP Object-Oriented Programming Practice Question
This PCAP practice question tests your understanding of object-oriented programming. 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.
Which TWO of the following are valid ways to define a class attribute that is shared among all instances?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Assign the attribute inside a classmethod using cls.
Option A is correct because a classmethod receives the class (cls) as its first argument, allowing you to assign or modify a class attribute via `cls.attribute = value`. This assignment affects the class itself, making the attribute shared among all instances, as the attribute is stored on the class object, not on instance dictionaries.
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.
✓
Assign the attribute inside a classmethod using cls.
Why this is correct
Classmethods can modify class attributes via the cls parameter.
Related concept
Read the scenario before looking for a memorised answer.
✗
Assign the attribute inside a staticmethod.
Why it's wrong here
Staticmethods do not have access to the class or instance.
✗
Use the @property decorator.
Why it's wrong here
Property creates a computed instance attribute, not a static class attribute.
✗
Assign the attribute inside __init__ using self.
Why it's wrong here
This creates an instance attribute, not a class attribute.
✓
Assign the attribute in the class body, outside any methods.
Why this is correct
This is the standard way to define a class attribute.
Related concept
Read the scenario before looking for a memorised answer.
Common exam traps
Common exam trap: answer the scenario, not the keyword
Python Institute often tests the distinction between class-level and instance-level attributes, and the trap here is that candidates confuse the @property decorator (which defines a computed instance property) with a class attribute, or think that a staticmethod can modify class state because it is defined inside the class body.
Detailed technical explanation
How to think about this question
Class attributes are stored in the class's __dict__ and are accessible via the class itself or any instance (unless shadowed by an instance attribute). When you assign inside a classmethod with `cls.attr = value`, you are modifying the class's __dict__ directly, which is why all instances see the change. A subtle behavior: if you assign the same attribute name via self in __init__, it creates an instance attribute that shadows the class attribute for that specific instance, which can lead to confusion if you expect shared state.
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 media company stores terabytes of video archives that are accessed once a year for audit purposes. Moving these objects to a cold storage tier (Azure Archive, S3 Glacier, or Google Nearline) costs a fraction of hot storage. Questions like this test whether you understand storage tiers, access frequency tradeoffs, and retrieval latency requirements.
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.
Object-Oriented Programming — This question tests Object-Oriented Programming — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Assign the attribute inside a classmethod using cls. — Option A is correct because a classmethod receives the class (cls) as its first argument, allowing you to assign or modify a class attribute via `cls.attribute = value`. This assignment affects the class itself, making the attribute shared among all instances, as the attribute is stored on the class object, not on instance dictionaries.
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.
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 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
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.