I Went to a Conference Last Week and Heard a Rumour

I went to a conference last week and heard a rumour that a friend of mine has spent time in jail.I told several people about the rumour and assured them it was untrue.My friend heard what I had done and became angry with me.Have I defamed him?

A) Yes.You can defame someone by repeating a rumour and insisting it was untrue.
B) No.You cannot defame someone unless you invented the rumour that attacked their reputation.
C) No.You cannot defame someone unless the words you used resulted in a clear and direct attack on their reputation.
D) Yes.You cannot defend someone from a rumour unless you have written permission from them to speak about it.