Yes, the Mongolian Empire is a correct answer for that reason.
Trajan, though, never actually conquered the site where Baghdad would eventually be founded. He got to the capital of the Parthian Empire (Ctesiphon) and went south, not north. In fairness, Trajan likely would’ve conquered Baghdad if it weren’t just sparsely populated farmland at the time. But no, there’s no evidence of any Roman presence in Baghdad’s archaeological digs.
The Mongol Empire conquered Baghdad from the Abbasid Caliphate
Otherwise, good quiz!
Trajan, though, never actually conquered the site where Baghdad would eventually be founded. He got to the capital of the Parthian Empire (Ctesiphon) and went south, not north. In fairness, Trajan likely would’ve conquered Baghdad if it weren’t just sparsely populated farmland at the time. But no, there’s no evidence of any Roman presence in Baghdad’s archaeological digs.