Q12. The plant parts which consist of two generations - one within the other
(a) Pollen grains inside the anther
(b) Germinated pollen grain with two male gametes
(c) Seed inside the fruit
(d) Embryo sac inside the ovule
4. (a) and (d)
Pollen grains inside the anther - Pollen grains represents male gametophytes.
Embryo sac inside the ovule - Embryo sac represents a female gametophyte.