An extra message added at the end of a letter after it is signed is called—

✅ কেন সঠিক: A postscript (P.S.) is an extra message added at the end of a letter after the signature.

❌ অন্য অপশন: A corrigendum is a correction; N.B. (nota bene) means ‘note well’; RSVP asks for a reply to an invitation.

💡 মনে রাখুন: P.S. = postscript; N.B. = nota bene; RSVP = répondez s’il vous plaît.

📖 শব্দার্থ: postscript — পুনশ্চ।