Solve the Problem $$( 7 m + 3 ) ^ { 2 }$$

Multiple Choice

Solve the problem.
- $$( 7 m + 3 ) ^ { 2 }$$

A) $7 m ^ { 2 } + 9$
B) $49 m ^ { 2 } + 42 m + 9$
C) $7 m ^ { 2 } + 42 m + 9$
D) $49 m ^ { 2 } + 9$