Correct Answer: (a) Bryophyta
Solution:There are two stages in the life cycle of Bryophyta, called sporophyte and gametophyte, which are structurally different. The gametophyte is the main plant, which is haploid. The gametophyte stage is free, green, branched, and long-lived, whereas the sporophyte stage is short-lived and completely dependent on the gametophyte.