Perform the Desired Operation $$( 6 + 7 i ) ( 6 - 7 i )$$

Multiple Choice

Perform the desired operation. Write the answer in the form a + bi.
- $$( 6 + 7 i ) ( 6 - 7 i )$$

A) $- 13$
B) $36 - 49 i ^ { 2 }$
C) 85
D) $36 - 49 \mathrm { i }$