Which of the Following Can Be Inserted to Make the Statement

Multiple Choice

Which of the following can be inserted to make the statement true? $$\arccos \left( \frac { \sqrt { 36 - x ^ { 2 } } } { 6 } \right) = \arcsin ( \quad ) , 0 \leq x \leq 6$$

A) $$\frac { x ^ { 2 } } { 6 }$$
B) $$\frac { x } { 6 }$$
C) $36 - x ^ { 2 }$
D) $\frac { \sqrt { 72 - x ^ { 2 } } } { x }$
E) x