Explanation:
Generally, heat flows from a hot environment to a cold (lesser temperature) environment. In this case, the soup is the hot environment and the air is the cold temperature.
Heat would continue to flow from one environment to another until thermal equilibrium is reached. At this thermal equilibrium, both environments would have the same temperature.
That table salt has a high melting point and mercury's melting point is low.
I am pretty sure the answer is D
