Explain this question

2. If $\overrightarrow{\mathrm{A}}+\overrightarrow{\mathrm{B}}=\overrightarrow{\mathrm{C}}$ and A + B = C then angle between $\overrightarrow{\mathrm{A}}$ and  $\overrightarrow{\mathrm{C}}$is
(A) $\frac{\mathrm{\pi }}{4}$
(B) $\frac{\mathrm{\pi }}{2}$
(C) 0
(D) 180°

Dear student ,
  on solving this que we find that angle bw A vector and B vector is zero,
then angle bw A vector and C vector will be equal to angle bw B vector and C,
 
 .
regards