**Concept:** The question tests on the basics of Mensuration.

**Solution:**

A new og 2021 question

Volume of X (V)= ∏r^2 h where r is the radius of X and h is the height of X.**St(1):-** The height of X is 20.

The statement does not provide us with any data on the value of "r" that is essential to calculate V. (Insufficient)**St(2):-** The base of X has area 25π.

The statement does not provide us with any data on the value of "h" that is essential to calculate V. (Insufficient)**Combining both we have**

h = 20 (from st(1) )

∏r^2 = 25 ∏

=> r = 5 units.

V = ∏r^2h and can be computed. **(Sufficient) option(C)**