According to the passage, what happened about 400 million years ago? A. Many terrestrial life-forms died out. B. New life-forms on land developed at a rapid rate. C. The megafossils were d
According to the passage, what happened about 400 million years ago?
A. Many terrestrial life-forms died out.
B. New life-forms on land developed at a rapid rate.
C. The megafossils were destroyed by floods.
D. Life began to develop in the ancient seas.