Write the Number as the Product of a Real Number $\sqrt { - 49 }$

Multiple Choice

Write the number as the product of a real number and i.
- $\sqrt { - 49 }$

A) $- \mathrm { i } \sqrt { 49 }$
B) $- 7 \mathrm { i }$
C) $7 \mathrm { i }$
D) $7 \sqrt { \mathrm { i } }$