Calculate $\int _ { C } ( 5 x \vec { i } + 3 y \vec { j } ) \cdot \vec { d A }$

Multiple Choice

Calculate $\int _ { C } ( 5 x \vec { i } + 3 y \vec { j } ) \cdot \vec { d A }$ where C is a cylinder of radius R with 0 $\le$ z $\le$ 1.

A) $8 \pi R ^ { 4 }$
B) $2 \pi R ^ { 3 }$
C) $8 \pi R ^ { 2 }$
D) $8 \pi R ^ { 3 }$
E) $8 R ^ { 3 }$