Which are the three cells found in a pollen grain when it is shed at the three celled stage?

Explanation

In 60% angiospermic plants, pollen grain is at two celled state (vegetative cell and generative cells) and in remaining species pollen grain is at three celled state at that time generative cell gets converted into two male gametes by under going mitosis. Thus in 3-celled state there is a vegetative cell and two male gametes.