Ray Promises to Give Steve His IPod in Exchange for Steve's

Multiple Choice

Ray promises to give Steve his iPod in exchange for Steve's promise to pay Ray $50. Later, they exchange the device for the funds. A contract was created when

A) ​Ray offered to sell his iPod.
B) ​Ray exchanged his iPod for $50.
C) ​Steve promised to pay Ray for the iPod.
D) ​Steve paid Ray $50 for the iPod.