Who broke the glass? The passive form of the sentence is-
Who have broken the glass?
Who have broken the glass by?
By whom was the glass being broken?
By whom was the glass broken?
Explanation:
Correct Answer is: By whom was the glass broken?
Who have broken the glass?
Who have broken the glass by?
By whom was the glass being broken?
By whom was the glass broken?
Correct Answer is: By whom was the glass broken?