Evaluate the Double Integral by First Identifying It as the Volume

Multiple Choice

Evaluate the double integral by first identifying it as the volume of a solid.
Select the correct answer.
$$\iint _ { R } ( 15 - 2 x ) d A , R = \{ ( x , y ) \mid 3 \leq x \leq 6,4 \leq y \leq 7 \}$$

A) 160
B) 260
C) 60
D) $- 140$
E) $- 40$