c
The formula for the pressure exerted by the liquid on the base is,
$P=\rho g h$
Rewrite the above equation.
$P=\left(\frac{m}{V}\right) g h$
$P=\left(\frac{m}{A \times h}\right) g h$
$P=\frac{g m}{A}$
The force exerted by the liquid is,
$F=P \times A$
$F=\left(\frac{g m}{A}\right) \times A$
$F=g m$
since the mass of the $A, B$ and $C$ are equal.
Therefore, $F_{A}=F_{B}=F_{C}$