From evolutionary point of view, retention of the female gametophyte with developing young embryo on the parent sporophyte for some time, is first observed in :

Solution & Explanation

Answer: (C) Pteridophytes. Solution: In heterosporous pteridophytes (e.g., Selaginella, Salvinia) the megaspore develops into a female gametophyte that is retained on the parent sporophyte, and the zygote develops into a young embryo within this retained female gametophyte — a precursor to the seed habit. This retention is FIRST seen in pteridophytes (evolutionarily earlier than gymnosperms); liverworts and mosses are bryophytes with a dominant free-living gametophyte and do not retain the gametophyte in this way. NCERT Reference: Class XI Biology, Plant Kingdom, p.32, lines 18-22 — "The female gametophytes in these plants are retained on the parent sporophytes for variable periods. The development of the zygotes into young embryos take place within the female gametophytes. This event is a precursor to the seed habit considered an important step in evolution."