Use the Product Rule to Simplify the Expression $x ^ { 7 } \cdot x ^ { 8 }$

Multiple Choice

Use the product rule to simplify the expression.
- $x ^ { 7 } \cdot x ^ { 8 }$

A) $x ^ { 56 }$
B) $2 x ^ { 56 }$
C) $2 x ^ { 15 }$
D) $x ^ { 15 }$