Find the Domain of X in the Expression $\sqrt { 1 - x ^ { 2 } }$

Multiple Choice

Find the domain of x in the expression $\sqrt { 1 - x ^ { 2 } }$ .

A) $( - \infty , - 1 ] \cup [ 1 , \infty )$
B) $( - \infty , 1 ]$
C) $[ - 1,1 ]$
D) $[ - 1 , \infty )$
E) $( - \infty , \infty )$