Concept:Uthman's death is unique because of the unusual manner in which he was killed.
Explanation:Caliph Uthman was not killed in battle, nor did he die naturally.
Rebels besieged him in his house and broke in.
He told his companions not to resist in order to save their lives.
The rebels stabbed him to death, and the killer was a slave.
His own copy of the Qur'an was soaked with his blood during the attack.
This makes his murder by a slave the unique feature of his death.
Answer:A. He was murdered by a slave.