When the Vector Sum of Three Co-Planar Forces $\overrightarrow { \mathrm { A } }$

When the vector sum of three co-planar forces, $\overrightarrow { \mathrm { A } }$ , $\vec { B }$ and $\overrightarrow { \mathrm { C } }$ ,is parallel to $\overrightarrow { \mathrm { A } }$ ,we can conclude that $\vec { B }$ and $\overrightarrow { \mathrm { C } }$

A) must sum to zero.
B) must be equal and opposite.
C) must have equal and opposite components perpendicular to $\overrightarrow { \mathrm { A } }$ .
D) must have equal and opposite components parallel to $\overrightarrow { \mathrm { A } }$ .
E) must have equal and opposite components parallel and perpendicular to $\overrightarrow { \mathrm { A } }$ .