According to the Second Law of Thermodynamics, heat cannot flow from:

The Second Law of Thermodynamics states that heat naturally flows from a hot source to a cold source, which is often described by the concept of entropy. In this context, the correct assertion is that heat cannot flow from a cold source to a hot source without the input of work. This is fundamentally due to the fact that energy naturally tends to disperse and spread out, moving from areas of higher concentration (hotter regions) to areas of lower concentration (colder regions).

When heat attempts to flow from a cold source to a hot source, it contradicts this natural direction of energy flow, which is energetically unfavorable. The only way to achieve this energy transfer is by doing work on the system, such as when a refrigerator or heat pump is used to extract heat from a cold space and transfer it to a warmer area. In such devices, work is done to reverse the natural flow of heat, allowing for the transfer against the temperature gradient.

This understanding fits within the framework of thermodynamic systems where the interplay of energy, heat, and work is crucial for analyzing the behavior of materials and processes in relation to temperature differences.