What Is the Radicand in the Expression $\sqrt { 9 x ^ { 10 } }$

Multiple Choice

What is the radicand in the expression? $\sqrt { 9 x ^ { 10 } }$

A) $9 x ^ { 10 }$
B) $x ^ { 10 }$
C) 9
D) $3 x ^ { 5 }$
E) $x ^ { 5 }$