Multiply and Simplify, If Possible $3 \sqrt { 3 } \sqrt { 15 }$

Multiple Choice

Multiply and simplify, if possible. $3 \sqrt { 3 } \sqrt { 15 }$

A) $3 \sqrt { 44 }$
B) $3 \sqrt { 5 }$
C) $9 \sqrt { 5 }$
D) $9 \sqrt { 42 }$
E) $3 \sqrt { 43 }$