Simplify the Expression Using the Products-To-Powers Rule $\left( - 3 x ^ { 2 } \right) ^ { 4 }$

Multiple Choice

Simplify the expression using the products-to-powers rule.
- $\left( - 3 x ^ { 2 } \right) ^ { 4 }$

A) $- 3 x ^ { 8 }$
B) $- 81 x ^ { 8 }$
C) $81 x ^ { 6 }$
D) $81 x ^ { 8 }$