Choose the correct sequence of events in a mango ovule leading to development of a diploid embryo via diplospory:

Correct option is A

Correct Answer: (a)
Explanation:
Diplospory is a form of apomixis in which the embryo sac (and hence the embryo) originates from an unreduced megaspore mother cell (2n) without undergoing meiosis. The megaspore mother cell directly gives rise to a diploid embryo sac, which then develops a diploid embryo (parthenogenetically). Sequence (a) shows archesporial differentiation in nucellus → megaspore mother cell → direct formation of embryo sac → diploid embryo, matching diplospory.
Information Booster:
Apomixis = asexual seed formation; diplospory is one apomictic pathway.
In diplospory the embryo sac remains diploid because meiosis is avoided or altered.
Parthenogenesis (development of embryo without fertilization) often follows diplospory.
Diplospory contrasts with meiotic sexual development (option b) which produces haploid megaspores and requires syngamy.
Examples of apomixis/diplospory occur in some angiosperms (mango shows agamospermy variants).