Who can solve the problem? (Passive)

The correct answer is “By whom can the problem be solved?” because this option correctly maintains passive voice structure while also forming a proper question.

Here’s a brief explanation of why this is the right choice:

    
• Passive Voice Structure: In passive voice, the focus is on the action and the recipient, rather than who performs the action. The phrase starts with "By whom," which is appropriate for asking about the doer in a passive construction.
    
• Correct Question Formation: The word order follows the standard interrogative form in English, where the auxiliary verb "can" comes before the subject, which is "the problem." Therefore, the entire structure flows correctly as a question.

Other options either mix tenses improperly or do not structure the question correctly in the passive form, which is why they are not suitable.

AI-এর ব্যাখ্যায় ভুল থাকতে পারে।