Generally, how many megaspores take part in the development of a female gametophyte in angiosperms?

The megaspore mother cell (MMC) undergoes meiotic division. Meiosis results in the production of four megaspores. In a majority of flowering plants, one of the megaspores is functional while the other three degenerate. Only the functional megaspore develops into the female gametophyte (embryo sac). This method of embryo sac formation from a single megaspore is termed monosporic development.