The pollen grain is

Options

A. An immature male gametophyte
B. A mature male gametophyte
C. Partially developed male gametophyte
D. Last stage of male gametophyte

Answer

C

Explanation

Pollen grain is partially developed male gametophyte and it becomes a mature male gametophyte when the generative cell divides by mitosis to form two sperm cells, in most species this process occurs after the pollen grain lands on the stigma of a carpel and pollen tube begins to form.