Write $\sqrt { - 294 }$ In Terms of I and Simplify

Multiple Choice

Write $\sqrt { - 294 }$ in terms of i and simplify.

A) $7 i \sqrt { 6 }$
B) $- 7 i \sqrt { 6 }$
C) $7 \sqrt { 6 }$
D) $42 i$
E) $- 7 \sqrt { 6 i }$