Q:  Which group of algae has been hypothesized to be the ancestor of plants?

A:  Charophytes

Q:  Which group of plants evolved most recently?

A:  Angiosperms

Q:  What main adaptation separated the pteridophytes from the bryophytes?

A:  lignin-hardened vascular tissues

Q:  In which group of plants did seeds first appear?

A:  gymnosperms