Question

which box represents the phase change \condensation\?

Explanation:

Condensation is the phase - change from gas to liquid. In phase - change diagrams, this is typically shown as an arrow going from the gas state to the liquid state.

Answer:

Without seeing the details of the boxes in the diagram clearly, but based on the concept of condensation as gas - to - liquid transition, if there is a box showing an arrow from a gas - labeled area to a liquid - labeled area, that would be the answer. However, since no clear details of what each box represents are given in the description, it's not possible to precisely identify the correct box among A, B, C, D. If we assume a standard phase - change representation, we need to look for an arrow from gas to liquid.