In mosses, the male gamete (sperm released from antheridia) fuses with the female gamete ( egg cells within the archegonium) to result in the immature sporophytes. The sporophyte matures and releases the spores. These spores germinate to form the protonema (an immature transitory stage), that matures into the gametophore (gamete bearing structure). Its tip branches to bear the male and the female gametophytes i.e antheridia and archegonia. So, in mosses, the gametophyte arises from spores produced from the sporophyte and the sporophyte arises from the fusion of gametes.So, the correct answer is 'Produces gametes that give rise to gametophyte'.