Which of the following statements are incorrect for megasporogenesis?

(i) Ovules generally differentiate a two single megaspore mother cell (MMC) in the micropylar region of the nucellus.

(ii) The MMC undergoes meiotic division, results is the production of four megaspores.

(iii) In a majority of flowering plants bisporic development occurs.

(iv) In a majority of flowering plants, one of the megaspores is functional while the other three degenerate.

(v) An ovule generally has a single embryo sac formed from a megaspore.

(vi) Typical angiosperm embryo sac at maturity is 8-nucleate and 7-celled.