What type of plant is thought to be the first plant? A. mosses
B. gymnosperms
C. ferns
D. angiosperms

Correct answer is A. mosses

The first land plants appeared around 470 million years ago, during the Ordovician period, when life was diversifying rapidly. They were non-vascular plants, like mosses and liverworts, that didn't have deep roots. About 35 million years later, ice sheets briefly covered much of the planet and a mass extinction ensued.

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