Part A is Stigma
Function : It is the terminal part of carpel, which may be sticky and helps in receiving the pollen grains from the another of stamen during pollination.
Part B is Pollen tube.
Function : The pollen tube grows out of the pollen grain through the style to reach the ovary.
Part C is female Germ cell.
Function : It is a female gametes which fuses with male gamete to form a diploid cell known as zygote.
