Solve the Problem $$( 9 r - 10 ) ( 9 r + 10 )$$

Multiple Choice

Solve the problem.
- $$( 9 r - 10 ) ( 9 r + 10 )$$

A) $9 r ^ { 2 } - 100$
B) $81 + 180 \mathrm { r } - 100 \mathrm { r } ^ { 2 }$
C) $81 r ^ { 2 } - 100$
D) $81 r ^ { 2 } - 180 r - 100$