Question

read the passage. then answer the question.
earth has an outer layer of rocks, or plates. these plates float on molten rock, which is in constant motion. first, the warmest material rises. then, it cools and sinks. finally, it warms and rises again.
its because of this motion that the plates move in different ways. they slide toward each other, away from each other, or across each other. however, all three movements are similar in that they can transform the landscape. mountains, volcanoes, and ocean trenches are formed from moving plates.
complete the sentence below by selecting a word or phrase from the drop - down menu.
the overall structure of this passage is

Explanation:

The passage first describes the motion of molten rock (cause) and then explains how this leads to plate movement and landscape transformation (effect). Words like "because" and the description of cause - effect relationships (motion of molten rock → plate movement → formation of mountains, etc.) support this.

Answer:

cause and effect