Correct option: D.Component of $\overrightarrow C$ along $\overrightarrow A = -$ component of $\overrightarrow D $ along $\overrightarrow A$
d
According to definition of $cross-product$
$\overrightarrow{\mathrm{C}}+\overrightarrow{\mathrm{D}}$ is perpendicular to both $\overrightarrow{\mathrm{A}}$ and $\overrightarrow{\mathrm{B}}$
i.e. $\quad \vec{A} \cdot(\vec{C}+\vec{D})=0$
or $\quad \overrightarrow{\mathrm{A}} \cdot \overrightarrow{\mathrm{C}}+\overrightarrow{\mathrm{A}} \cdot \overrightarrow{\mathrm{D}}=0$
or $\quad$ A (component of $\overrightarrow{\mathrm{C}}$ along $\overrightarrow{\mathrm{A}}$ ) $+\mathrm{A}$
(component of $\overrightarrow{\mathrm{D}} \text { along } \overrightarrow{\mathrm{A}})=0$
or component of $\overrightarrow{\mathrm{C}}$ along $\overrightarrow{\mathrm{A}}$
$=$ $-$ component of $\overrightarrow{\mathrm{D}}$ along $\overrightarrow{\mathrm{A}}$