Question

Which answer is equal to -2i*(-2i)? A) 4 B) -4 C) 4i D) -4i

Answer 1

I got letter B which is -4

Answer 2

$\bf \textit{recall that }i^2=-1\qquad therefore \\\\\\ -2i(-2i)\implies +2^2i^2\implies 4(-1)\implies -4$