Question 1hardmultiple choice
Full question →hardmultiple choiceObjective-mapped
A financial services company is evaluating distributed NoSQL databases for a new application that must remain fully available even during network partitions. The application can tolerate stale reads for some types of queries. Which statement accurately describes the trade-off described by the CAP theorem in this context?
Answer choices
Why each option matters
Good practice is not just finding the correct option. The wrong answers often show the exact trap the exam wants you to fall into.
A
Distractor review
During a network partition, the system can maintain both consistency and availability.
According to the CAP theorem, during a partition, a distributed system must choose between consistency and availability; it cannot provide both.
B
Best answer
When a network partition occurs, a distributed system must choose between providing consistency and providing availability.
This is the core trade-off of the CAP theorem: during a partition, you must sacrifice either consistency (to stay available) or availability (to remain consistent).
C
Distractor review
Partition tolerance is an optional property and can be sacrificed to achieve both consistency and availability.
In distributed systems, partitions are inevitable; therefore, partition tolerance is a requirement, not optional. Sacrificing it would mean the system stops when a partition occurs.
D
Distractor review
Availability guarantees that every read returns the most recent write.
Availability in CAP means every request gets a response (not an error), but that response may not contain the latest write. The property that ensures the latest write is returned is consistency.
Common exam trap
Common exam trap: answer the scenario, not the keyword
Many certification questions include familiar terms but test a specific constraint. Read the exact wording before choosing an answer that is generally true but wrong for this case.
Technical deep dive
How to think about this question
This question should be treated as a scenario, not a definition check. Identify the problem, the constraint and the best action. Then compare each option against those facts.
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.
- Use explanations to understand the rule behind the answer.
TExam Day Tips
- Underline the problem statement mentally.
- 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.
Related practice questions
Related DP-900 practice-question pages
Use these pages to review the topic behind this question. This is how one missed question becomes focused revision.
More questions from this exam
Keep practising from the same exam bank, or move into a focused topic page if this question exposed a weak area.
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FAQ
Questions learners often ask
What does this DP-900 question test?
Read the scenario before looking for a memorised answer.
What is the correct answer to this question?
The correct answer is: When a network partition occurs, a distributed system must choose between providing consistency and providing availability. — The CAP theorem states that in a distributed data store, it is impossible to simultaneously provide more than two of the following guarantees: Consistency (every read receives the most recent write or an error), Availability (every request receives a non-error response, without guarantee that it contains the most recent write), and Partition tolerance (the system continues to operate despite network partitions). In this scenario, the application prioritizes availability and partition tolerance, meaning it is an 'AP' system. When a partition occurs, the system chooses availability over consistency, allowing stale reads.
What should I do if I get this DP-900 question wrong?
Then try more questions from the same exam bank and focus on understanding why the wrong options are tempting.
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