The plant parts which consist of two generations – one within the other

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

(1) (a), (b) and (c) (2) (c) and (d) (3) (a) and (d) (4) (a) only