Find the Modulus and the Argument for the Complex Number $z = - i$

Multiple Choice

Find the modulus and the argument for the complex number. $z = - i$

A) $r = - 1 , \theta = \pi / 2$

B) $r = 1 , \theta = \pi$

C) $r= i , \theta = 0$

D) $r= \sqrt { 2 } , \theta = 3 \pi / 2$

E) $r = 1 , \theta = 3 \pi / 2$