Correct Answer: By whom were my glasses broken?

Solution : The correct answer is the fourth option ​​​​​.

The original sentence is in the active voice, in which the subject "who" is performing the action, as the subject is the doer in the active voice, whereas the passive voice is the voice in which the object experiences an action rather than the person who acts. Hence, the object in the active sentence becomes the subject in the passive voice.

The passive structure for the above interrogative sentence is: "By whom (agent) + were (auxiliary verb) + my glasses (object) + broken (past participle form of the main verb)?"

The correct option that expresses the given sentence in passive voice is: " By whom were my glasses broken?"