Use the Product Rule to Multiply $\sqrt { 28 } \cdot \sqrt { 7 }$

Multiple Choice

Use the product rule to multiply. Assume all variables represent positive real numbers.
- $\sqrt { 28 } \cdot \sqrt { 7 }$

A) 196
B) 14
C) $2 \sqrt { 7 }$
D) $7 \sqrt { 2 }$