Four cuboids, each having the same length, breadth and height, are placed in water. They are maintained at an equal depth and in the same orientation by vertical rods, as illustrated. Water has density $\rho$. Cuboid $W$ is made of a material with density $4\rho$. Cuboid $X$ is made of a material with density $2\rho$. Cuboid $Y$ is made of a material with density $\rho$. Cuboid $Z$ is made of a material with density $0.5\rho$. Which statement is correct?
- AThe upthrust of the water on each of the cuboids is the same.
- BThe upthrust of the water on $W$ is twice the upthrust of the water on $X$.
- CThe upthrust of the water on $X$ is twice the upthrust of the water on $W$.
- DThe upthrust of the water on $Y$ is zero.