During Wegener’s time, scientists thought land bridges linked continents together. The land bridges then became submerged underwater.
Wegener argued that if land bridges had existed, they would not remain submerged.

Which observation caused Wegener to argue this point?

A. The rocks that formed continents warmed more quickly than the rocks that formed the ocean floor.

B. The rocks that formed continents warmed more slowly than the rocks that formed the ocean floor.

C. The rocks that formed continents were denser than the rocks that formed the ocean floor.

D. The rocks that formed continents were less dense than the rocks that formed the ocean floor.

PLEASE HELP, dumby here doesn't know the answer