Question

seed habit first time is originat d in which group of plants
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Answer 1

It was developed in fossil gymnosperm of group Cycadofilicales (pteridosperms), i.e. Seed ferns, e.g. Lyginopteris which bears characters of cycads and ferns both, Seed habit is shown by few pteridophytes like Selaginella, Marselia, Isoetes, etc.