It is called relevant.
Relevant is just a synonym to related, so if it's not related to the subject than it would be irrelevant.
The situation wherein summarizing would be the most useful is writing a synopsis of a play. The correct answer is option B. The word synopsis means a brief summary or outline, which emphasizes on the general points and view of the overall story of a book, play, or a movie.
Map .this is the answer.if not then no.d.