Question

Fill in the blank with the most appropriate word.
I was startled ______the loud knocking on the door.

• A. at
• B. on
• C. by
• D. with

Answer 1

The correct option is C by

Option C is the correct answer because 'by' is used usually after a passive verb, to show who or what does, creates or causes something.

Options A, B and D are incorrect 'at' is used to point out a specific time or a specific place, 'on' is used to express a surface of something or place or location and 'with' is used to indicate being together or being involved.