1Z0-829 Working with Arrays and Collections Practice Question
This 1Z0-829 practice question tests your understanding of working with arrays and collections. 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 statement about Collection interface remove methods is correct?
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Collection.remove(Object) removes the first occurrence and returns boolean.
The correct answer is A because the Collection interface's remove(Object) method removes the first occurrence of the specified element from the collection, if present, and returns true if the collection was modified (i.e., the element was found and removed). This behavior is defined in the Java Collections Framework and applies to all implementations of Collection, such as ArrayList and HashSet.
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.
✓
Collection.remove(Object) removes the first occurrence and returns boolean.
Why this is correct
Correct behavior for remove method in Collection.
Related concept
Read the scenario before looking for a memorised answer.
✗
List.remove(int) removes element at index and returns the removed element.
Why it's wrong here
This method is in List interface, not Collection.
✗
Collection.remove(Object) removes all occurrences of the element.
Why it's wrong here
It removes only the first occurrence and returns true if an element was removed.
✗
Both B and C
Why it's wrong here
C is not a method of Collection, so D is incorrect.
Common exam traps
Common exam trap: answer the scenario, not the keyword
The trap here is that candidates often confuse the Collection interface's remove(Object) with the List interface's remove(int), mistakenly thinking that remove(Object) removes all occurrences or that the index-based remove is part of the Collection interface.
Detailed technical explanation
How to think about this question
Under the hood, Collection.remove(Object) relies on the equals() method of the element to locate the first matching object, iterating through the collection's elements. For collections that allow duplicates (like List), only the first occurrence is removed, while for Set implementations, there is only one occurrence anyway. A subtle behavior is that if the collection is modified during iteration (e.g., via an iterator's remove), a ConcurrentModificationException may be thrown, but the direct remove(Object) method is safe and does not cause this issue.
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 practitioner preparing for the 1Z0-829 exam encounters this exact type of scenario on the job. The correct answer here is not the most general option — it is the best answer for the specific constraint described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Real exam questions reward reading the full scenario before eliminating options, because the constraint defines which answer fits.
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.
Working with Arrays and Collections — This question tests Working with Arrays and Collections — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Collection.remove(Object) removes the first occurrence and returns boolean. — The correct answer is A because the Collection interface's remove(Object) method removes the first occurrence of the specified element from the collection, if present, and returns true if the collection was modified (i.e., the element was found and removed). This behavior is defined in the Java Collections Framework and applies to all implementations of Collection, such as ArrayList and HashSet.
What should I do if I get this 1Z0-829 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 1Z0-829 practice question is part of Courseiva's free Oracle 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 1Z0-829 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.