Ian, a Carpenter, Repaired Sally's Deck and Sent Her a Bill

Multiple Choice

Ian, a carpenter, repaired Sally's deck and sent her a bill for $500, accompanied with a note: "Sally, instead of paying me, pay the $500 to the Humane Society as a donation from me." If the Humane Society doesn't get paid, it may sue:

A) Ian
B) Sally
C) Ian or Sally
D) The Humane Society cannot sue either Ian or Sally