Final answer:
Plate tectonics directly cause the folding of rock layers.
Step-by-step explanation:
The direct effect of plate tectonics is the folding of rock layers. As tectonic plates move and interact, they exert pressure on the rocks, causing them to fold and form mountain ranges. For example, the Himalayas were formed by the collision of the Indian and Eurasian plates, resulting in the folding of rock layers and the formation of tall mountains.
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