Which statement about tectonic plates is true?

Which statement about tectonic plates is true?

• A. Oceanic plates are denser and thicker than continental plates
• B. Oceanic plates are less dense but thicker than continental plates
• C. Continental plates are more dense than oceanic plates
• D. Continental plates are less dense but thicker than oceanic plates

Answer: (D)

The statement reflects how density and thickness of crust control how plates behave at boundaries. Oceanic crust is formed from basaltic rocks that are denser and thinner, while continental crust is granitic, less dense, and much thicker. Because continental crust is less dense, it sits higher and thicker on the mantle, whereas the denser, thinner oceanic crust tends to subduct beneath it when they interact. That’s why the correct statement is that continental plates are less dense but thicker than oceanic plates. The other ideas don’t fit because oceanic crust is not thicker and continental crust is not more dense than oceanic crust.

The statement reflects how density and thickness of crust control how plates behave at boundaries. Oceanic crust is formed from basaltic rocks that are denser and thinner, while continental crust is granitic, less dense, and much thicker. Because continental crust is less dense, it sits higher and thicker on the mantle, whereas the denser, thinner oceanic crust tends to subduct beneath it when they interact. That’s why the correct statement is that continental plates are less dense but thicker than oceanic plates. The other ideas don’t fit because oceanic crust is not thicker and continental crust is not more dense than oceanic crust.