The Vector $\overrightarrow{\mathbf{r}}$ Indicates the Instantaneous Displacement of a Projectile from the Origin

Multiple Choice

The vector $\overrightarrow{\mathbf{r}}$ indicates the instantaneous displacement of a projectile from the origin. At the instant when the projectile is at $\overrightarrow{\mathbf{r}}$ , its velocity and acceleration vectors are $\overrightarrow{\mathbf{v}}$ and $\overrightarrow{\mathbf{a}}$ . Which statement is correct?

A) $\overrightarrow{\mathbf{v}}$ is always perpendicular to $\overrightarrow{\mathbf{r}}$ .
B) $\overrightarrow{\mathbf{a}}$ is always perpendicular to $\overrightarrow{\mathbf{r}}$ .
C) $\overrightarrow{\mathbf{a}}$ is always perpendicular to $\overrightarrow{\mathbf{v}}$ .
D) $\overrightarrow{\mathbf{a}}$ is always perpendicular to $\overrightarrow{\mathbf{V}}_{x}$ .
E) $\overrightarrow{\mathbf{a}}$ is always perpendicular to $\overrightarrow{\mathbf{v}}_{y}$ .