Final answer:
The moisture forming on the inside of the plastic wrap in the student's model represents condensation, which is part of the water cycle where water vapor cools and changes back into liquid form.
Therefore , option B is correct.
Step-by-step explanation:
The change the student is most likely observing in this model is condensation. When the model is placed near a sunny window, the water in the cup warms up and evaporates. As the water vapor rises and comes into contact with the cooler plastic wrap, it cools down. The cooling causes the water vapor to change back into liquid water, leading to droplets forming on the inside of the plastic wrap. This process is akin to how water vapor in the atmosphere cools and condenses to form clouds, which can lead to precipitation.
Condensation is the process in which water vapor changes to tiny droplets of liquid water. When the water vapor in the air cools inside the model, it condenses and forms moisture on the inside of the plastic wrap.