Answer:
Option C, stays the same
Explanation:
Heat flow by vibrating the molecules in any medium. Therefore, some medium is essential for heat transfer and hence no heat flows across an insulated vacuum can. Without any medium, heat transfer is stopped which means that neither the heat from outside environment can flow into the can nor it can flow from the can into the external environment.
Hence, the heat contained within the can shall remain the same.
Thus, option C is correct
