Option A is the correct answer.
Step-by-step explanation:
Pressure is the ratio of normal force to the area.
![\texttt{Pressure = }\frac{\texttt{Normal force}}{\texttt{Area}}](https://img.qammunity.org/2020/formulas/physics/middle-school/61miknjipxkq751wl6yvfh3nktsuh96as0.png)
Force = Pressure x Area
Area = 500 cm² = 0.05 m²
Pressure = 4000 Pa
Force = 0.05 x 4000 = 200 N
We know that
Work done = Force x Displacement
W = F x d
Displacement, d = 30 cm = 0.3 m
W = 200 x 0.3 = 60 Joules.
Option A is the correct answer.