In an orbital motion, the angular momentum vector is:

Correct option is D

​$$\text{In orbital motion,} \ \textbf{angular momentum} \ \text{is a vector quantity defined as:}\\[1em]\vec{L} = \vec{r} \times \vec{p}\\[1em]\text{Where:} \\\bullet\ \vec{L} = \text{Angular momentum vector} \\\bullet\ \vec{r} = \text{Position (radius) vector} \\\bullet\ \vec{p} = m \vec{v} = \text{Linear momentum vector}\\[1em]\text{The \textbf{cross product} } \vec{r} \times \vec{p} \text{ means the resulting vector } \vec{L} \text{ is \textbf{perpendicular} to both the radius vector and the momentum vector.}$$​​