Question

10. There was a knock _____ the door. (A) of (B) in (C) at (D) for

Answer 1

С) at. Перевод:В дверь постучали. )))))))))))))))))))))

Answer 2

The correct preposition to use in this context is "at." So, the complete sentence would be:

"There was a knock at the door."

In this case, the preposition "at" is used to indicate the location or direction of the action, which is the knock. "At the door" means the knocking sound occurred in the direction of the door.