Which of the following is not a Protection system ?

A. None of the mentioned

B. System to shut down a reactor if temperature/pressure are too high

C. System to indicate not returning of the library book

D. System to stop a train if it passes a red light

Found an error? Read our corrections policy and submit a sourced correction below. You can also share a useful explanation in your own words.

Discuss the answer or suggest a sourced correction
Thank you for contributing.
Your comment was submitted and will appear after editorial review.

Your email is used only for moderation and is never displayed. Spam, copied material and fabricated endorsements are rejected.