Question

Out of the four alternatives, choose the one which expresses the sentence below in passive voice.

Who gave you permission to enter?

• A. By whom you were given permission to enter?
• B. Who was given you permission to enter?
• C. By whom were you given permission to enter?
• D. By whom were you give permission to enter?

Answer 1

The correct option is C By whom were you given permission to enter?

While converting into passive voice, "who" is converted into "by whom".
And $V_2+$ object is converted into helping verb $+$ object $+V_3$

Correct passive voice is :
By whom were you given permission to enter?