Aashka . . . . . . . . there before a week. A. did B. was C. which D. when

The correct answer is B. was.

Aashka was there before a week. This means that Aashka was in a particular place at a time in the past that is one week before the present time.

The other options are incorrect because:

• A. did does not make sense in this context.
• C. which is used to introduce a relative clause, which is not needed in this sentence.
• D. when is used to ask about the time of an event, which is not what is being asked in this sentence.