The volume \( V \) of a cylinder is calculated using the formula:
\[ V = \pi r^2 h \]
where \( r \) is the radius of the base and \( h \) is the height. For the given cylinder with a base radius of \( 2.5 \) inches and a height of \( 9 \) inches, you can substitute these values into the formula:
\[ V = \pi (2.5)^2 (9) \]
This means the correct expression for the volume of the cylinder is:
\[ \pi (2.5)^2 (9) \text{ in}^3 \]
Thus, the correct response from the options provided is:
\(\pi (2.5)^2 (9) \text{ in}^3\)