Which of the following options is a better purchase for a microwave?

option 1: a cash sale for $120

option 2: $5 down with equal payments of $10 for 15 weeks

option 3: $10 down with equal payments of $5 for 24 months

option 4: $0 down with equal payments of $15 for 9 months

a. option 2
b. option 1
c. option 3
d. option 4