The answer is detective control. The alarm is a detective control because it identifies and alerts personnel to a security breach after it has occurred—in this case, the door being left open too long—rather than preventing the action or correcting the violation. This aligns with the core Security+ SY0-701 objective on control types, where detective controls are defined by their ability to monitor and notify, not to block or remediate. On the exam, a common trap is confusing detective controls with preventive controls, such as the badge reader itself, which physically restricts access. A useful memory tip is to think of a smoke alarm: it doesn’t stop the fire, but it detects and warns you—just like this door alarm detects the open door and alerts security.
SY0-701 General Security Concepts Practice Question
This SY0-701 practice question tests your understanding of general security concepts. 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.
A restricted server room opens only with a badge, and an alarm sounds if the door is left open too long. Which control type is the alarm?
Why wrong: A preventive control stops the event, but the alarm activates after the issue begins.
B
Detective control
A door alarm is a detective control because it alerts staff after a condition occurs, such as the door being left open too long or forced open. It helps security personnel notice a problem quickly so they can respond. In this scenario, the badge controls access, while the alarm detects an abnormal state and signals that action is needed.
C
Corrective control
Why wrong: A corrective control fixes a problem after it happens, but the alarm itself only reports the issue.
D
Deterrent control
Why wrong: A deterrent control discourages bad behavior, but an alarm primarily detects and announces a problem.
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Detective control
The alarm is a detective control because it detects and alerts when a door is left open too long, indicating a potential security breach. It does not prevent the door from being opened or correct the situation; it simply notifies personnel of an ongoing or past violation.
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.
✗
Preventive control
Why it's wrong here
A preventive control stops the event, but the alarm activates after the issue begins.
✓
Detective control
Why this is correct
A door alarm is a detective control because it alerts staff after a condition occurs, such as the door being left open too long or forced open. It helps security personnel notice a problem quickly so they can respond. In this scenario, the badge controls access, while the alarm detects an abnormal state and signals that action is needed.
Related concept
Read the scenario before looking for a memorised answer.
✗
Corrective control
Why it's wrong here
A corrective control fixes a problem after it happens, but the alarm itself only reports the issue.
✗
Deterrent control
Why it's wrong here
A deterrent control discourages bad behavior, but an alarm primarily detects and announces a problem.
Common exam traps
Common exam trap: answer the scenario, not the keyword
CompTIA often tests the distinction between detective and corrective controls, and the trap here is that candidates mistakenly think the alarm 'corrects' the situation by alerting, but corrective controls actually take action to restore security, such as automatically closing the door.
Detailed technical explanation
How to think about this question
The alarm typically uses a door position sensor (e.g., a magnetic reed switch) connected to an access control system (ACS) that monitors the door's open/close state. When the door remains open beyond a configurable threshold (often 30–60 seconds), the ACS triggers an audible or visual alarm, and may also send an alert to a security management platform via SNMP or syslog. In real-world scenarios, this alarm helps enforce security policies by prompting immediate investigation, but it does not automatically lock the door or prevent the initial access.
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 security analyst at a medium-sized enterprise encounters this scenario during an investigation or architecture review. The correct answer reflects best practice for the specific threat or control described. Answer the scenario, not the keyword: identify the specific constraint before choosing the most familiar-sounding option. Security exam questions test whether you can match controls to threats in context — not just recall definitions.
Related glossary terms
Concepts from this question explained
These glossary pages explain the core terms tested in this SY0-701 question in full detail.
General Security Concepts — This question tests General Security Concepts — Read the scenario before looking for a memorised answer..
What is the correct answer to this question?
The correct answer is: Detective control — The alarm is a detective control because it detects and alerts when a door is left open too long, indicating a potential security breach. It does not prevent the door from being opened or correct the situation; it simply notifies personnel of an ongoing or past violation.
What should I do if I get this SY0-701 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 SY0-701 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 SY0-701 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.