Could you please choose the answer and explain to me?
The preparations............by the time the guests..............

A. had been finished/ arrived
B. have finished / arrived
C. had finished / were arriving
D. have been finished / were arrived.

Question

Could you please choose the answer and explain to me?
The preparations............by the time the guests..............

A. had been finished/ arrived
B. have finished / arrived
C. had finished / were arriving
D. have been finished / were arrived.

Answer

Answer: A had been finished/arrived

We use the Past Perfect Continuous tense to show that something started in the past and continued up until another time in the past.