Answer: B. X and Z
Explanation:
There are three modes by which heat can be transferred. Heat always transfers from hotter object to colder object.
Conduction occurs when there is contact between hotter body and colder body. The molecules vibrate at their position and transfer heat to the neighboring molecules. In the diagram conduction takes place at X and Z. The heat transfers from pan to handle at X and then from handle to hand at Z.
Convection occurs in fluid. Bulk motion of fluid carries energy. Like in area W in the diagram.
Radiation does not require medium to transfer energy. Like in area Y marked in the diagram.