If complex numbers $z_1,z_2,z_3$ represents vertices of an equilateral triangle and $\mid z_1\mid=\mid z_2\mid=\mid z_3\mid$ then
$\begin{array}{1 1} (A) z_1+z_2+z_3=0 \\(B) z_1+z_2+z_3 \neq 0 \\ (C) z_1+z_2+z_3=\large\frac{\sqrt 3}{4}\normalsize z_1 \\ (D) None\; of\; these \end{array}$