Identity the Constants Numerical Coefficients, and Variables in the Expression $\pi \mathrm { r }$

Multiple Choice

Identity the constants numerical coefficients, and variables in the expression $\pi \mathrm { r }$ .

A) r, variable
B) $\pi$ , constant and numerical
C) $\pi$ , constant and numerical coefficient: r, constant
D) $\pi$ , constant and numerical coefficient: r, variable
E) data insufficient