Which of the following statements is true for work done by conservative forces?

As shown in the diagram, a particle is to be carried from point $A\text{ to} C$ via paths $\left(\mathrm{I}\right), \left(\mathrm{II}\right)\text{ and} \left(\mathrm{III}\right)$ in gravitational field, then which of the following statements is correct.

For the path PQR in a conservative force field the amounts work done in carrying a body from P to Q and from Q to R are 5 Joule and 2 Joule respectively. The work done in carrying the body from P to R will be