Find the Volume of the Described Solid $x$ -Axis At $x = - 2$

Find the volume of the described solid.
-The solid lies between planes perpendicular to the $x$ -axis at $x = - 2$ and $x = 2$ . The cross sections perpendicular to the $x$ -axis are circles whose diameters stretch from the curve $y = - 7 / \sqrt { 4 + x ^ { 2 } }$ to the curve $y = 7 / \sqrt { 4 + x ^ { 2 } }$ .

A) $49 \pi$
B) $\frac { 7 } { 4 } \pi ^ { 2 }$
C) $49 \pi ^ { 2 }$
D) $\frac { 49 } { 4 } \pi ^ { 2 }$