A cylinder with a top and bottom has radius $3x+1$ and height $x-2$. The simplified expression for its surface area is

Question

$\begin{array}{1 1} (a)\; \pi[12x^2-x+1] \;sq.units \\ (b)\;2\pi[12x^2-x+1] \;sq.units \\ (c)\; 2\pi[12x^2-x-1] \; sq. units \\(d)\; 2 \pi [12x^2+x-1] sq.units \end{array}$