The angle between $(\overrightarrow{P}+\overrightarrow{Q})$ and $(\overrightarrow{P}+\overrightarrow{Q})$ is

Question

$\begin{array}{1 1}(A)\;0^{\circ} \\(B)\;\pi/4 \\(C)\;\pi/2 \\(D)\;\pi \end{array}$