Find the odd one out among the following structures?

The correct answer is Option (3) → Megaspore

Option (1) Tapetum — A structure of the male side (the anther). The tapetum is the innermost wall layer of the microsporangium (pollen sac). Its cells nourish the developing pollen grains.

Option (2) Microspore — A structure of the male side (the anther). A microspore is formed when a microspore mother cell in the anther divides by meiosis. Each microspore develops into a pollen grain.

Option (3) Megaspore — A structure of the female side (the ovule). A megaspore is formed when the megaspore mother cell in the ovule divides by meiosis. Usually one of the four megaspores is functional and develops into the embryo sac, the female gametophyte.

Option (4) Generative cell — A structure of the male side (the anther). The generative cell is the small cell inside the pollen grain. It divides to form the two male gametes.