The arrows in the diagram should be labeled as follows:
A: Warm water rises to the top of the pot.
B: Cool water sinks to the bottom of the pot.
C: Convection current.
D: Heat applied to the pot
A: This arrow represents the movement of the heated water upwards. As the water near the heat source becomes warmer, its molecules move more quickly and spread out, making it less dense.
B: This arrow stand for the movement of the cooler water downwards. As the warm water rises to the top, the cooler water at the top of the pot descends to the bottom of the pot.
C: This arrow represents the overall circular motion of the heated water rising and the cooler water sinking.
D: This arrow represents the heat source that is driving the convection current. In this case, the heat is being applied to the bottom of the pot by the stove, causing the water at the bottom to heat up and start the convection process.