It must be finished . . . . . . . . Friday afternoon.

A. by

B. of

C. at

D. on

Answer: Option A

Solution(By Examveda Team)

As a preposition of time, 'by' means before a specific time. 'By' shows a time limit for something to happen. An event must happen before a specific time is reached. For example - Please send me the report by Tuesday.