What is hydrostatic paradox?

Explanation

Hydrostatic paradox: This is useful to prove that the liquid pressure is in the same at all points at the same horizontal level.

Consider three vessels A,B and C of different shapes as shown in the figure. They are connected at the bottom by a horizontal pipe. On filling with water, the level in the three vessels is the same though they hold different amounts of water. This is so, because water at the bottom has the same pressure below each section of the vessel.
Thus, it proves that the height of the fluid column is independent of the cross sectional or base area and the shape of the container.