Answer:
C. Deposition of sand onto the beach during summer
D. Erosion of sand from the beach during winter
Explanation:
The model described illustrates the annual cycle of changes on sandy beaches due to the action of water, contrasting the effects of rough waters in winter with calm waters in summer. During the winter, rough waters lead to the erosion of sand from the beach, which is then stored offshore. This process is an example of erosion, where materials are worn away and transported from one location to another. In the summer, calm waters facilitate the deposition of sand back onto the beach, where it accumulates and is stored. This is an example of deposition, a process where materials are added to a landform. Hence, the two types of changes to Earth's surface illustrated in the model are deposition of sand onto the beach during summer (C) and erosion of sand from the beach during winter (D).
