“Who planted this tree here?” The correct passive voice of this sentence is—

✅ কেন সঠিক: The correct passive is ‘By whom was this tree planted here?’ None of the options gives exactly this: the question form needs ‘was’ before the subject.

❌ অন্য অপশন: Option (a) keeps statement order (‘the tree was’), (b) and (d) use wrong tenses (‘had been’), and (c) is an informal echo question rather than standard passive form.

💡 মনে রাখুন: Who + V2 (active) → By whom + was/were + object + V3 (passive).

📖 শব্দার্থ: অর্থ: এই গাছটি এখানে কে লাগিয়েছিল? — শুদ্ধ passive: By whom was this tree planted here?