Correct Answer - C
Let the radius of the cylinder be r units and height of it be h units.
Then the volume of the cylinder `= pi r^(2) h` cubic-units when the radius is halved, i.e., `r/2` units and the height is doubled, i.e., 2h units, then the volume becomes `pi ( r/2)^(2)xx2h` cubic-units `=pixx(r^(2))/(4)xx2h` cubic-units `=(pi r^(2)h)/(2)` cubic-units
So, the volume will be half.
`:.` (c) is correct.
