Peter, a High School Student with a Part-Time Job, Saves

Peter, a high school student with a part-time job, saves some money each payday, believing that it will provide him with the purchasing power to buy books and pay tuition when he attends college in two years. He is relying heavily on money as a:

A) unit of account.
B) store of value.
C) medium of exchange.
D) standard of deferred payment.