Use a Calculator to Evaluate the Expression $19 ^ { 2 } - 16 ^ { 2 } - \left( 18 ^ { 2 } - 15 ^ { 2 } \right)$

Use a calculator to evaluate the expression. $19 ^ { 2 } - 16 ^ { 2 } - \left( 18 ^ { 2 } - 15 ^ { 2 } \right)$

A) 16
B) 9
C) $6$
D) 10
E) 11