Multiply and Then, If Possible, Simplify by Factoring $\sqrt{2 x^{4}} \sqrt{14 x^{6}}$

Multiple Choice

Multiply and then, if possible, simplify by factoring.
- $\sqrt{2 x^{4}} \sqrt{14 x^{6}}$

A) $2 \sqrt{7 x^{10}}$
B) $2 x^{10} \sqrt{7}$
C) $4 x^{5} \sqrt{7}$
D) $2 x^{5} \sqrt{7}$