An object with weight $W$ is hung from a newton meter. When the object is fully immersed in water, the newton meter shows $P$. When the object is fully immersed in oil, the newton meter shows $Q$. What is the ratio $\dfrac{\text{density of oil}}{\text{density of water}}$?
- A$\dfrac{W - P}{Q - P}$
- B$\dfrac{Q - P}{W - P}$
- C$\dfrac{W - P}{W - Q}$
- D$\dfrac{W - Q}{W - P}$