Explanation

D is correct because Ali ibn Abi Taalib was the Prophet's cousin and son-in-law (married to Fatima). A is incorrect because Abu’l-Aas ibn al-Rabee was a prominent figure but not known as the third son-in-law. B is incorrect because Utbah ibn Abi Lahab was an enemy of the Prophet. C is incorrect because Usmaan ibn Affaan was a companion and later Caliph, but not typically cited as the third son-in-law in this context.