Solve the Problem $\$ 39$ , Plus $\$ 0.07$ Per Mile to Rent a Moving Truck for a Day

Solve the problem.
-A truck rental company charges $\$ 39$ , plus $\$ 0.07$ per mile to rent a moving truck for a day. If $x$ represents the number of miles driven and $f(x)$ represents the total cost to rent the truck for a day, write a linear function that models the situation.

A) $f(x) =0.07 x-39$
B) $f(x) =0.07 x+39 x$
C) $f(x) =39 x+0.07$
D) $f(x) =0.07 x+39$