There are two jars in which one is filled with hot air and the other one with cold air. Now the jar with cold air is inverted and placed right on top of the jar with hot air. What will happen immediately?

Question

$\begin{array}{1 1} (a)\; \text{hot air moves upward} \\ (b)\; \text{hot air remains in the same jar} \\ (c)\; \text{the jar will burst} \\ (d)\; \text{cold water gets heated} \end{array}$