Steven Owes Tina $100 for a Used Computer Which He

Multiple Choice

Steven owes Tina $100 for a used computer which he bought last year at Tina's garage sale.The two agree that the debt can be paid by Steven's shoveling snow from Tina's driveway from January through March.The new contract is a(n) :

A) accord.
B) satisfaction.
C) novation.
D) rescission.