Multiply and Leave Your Answer in Exponent Form $$\left( x ^ { 3 } \right) \left( x ^ { 4 } \right)$$

Multiply and leave your answer in exponent form.
- $$\left( x ^ { 3 } \right) \left( x ^ { 4 } \right)$$

A) $( 2 x ) ^ { 7 }$
B) $x ^ { 7 }$
C) 2x⁷
D) $x ^ { 12 }$