It takes Rebekka 1/2 hour to jog 1 1/4 miles.
Which calculation could be used to find her unit rate in miles per hour?

A. multiply: 1 1/4 x 1/2
B. multiply: 1/2 x 2
C. divide: 1 1/4 / 1/2
D. divide: 1/2 / 1 1/4