Answer: Option D
:
D
Pre-fertilisation events in sexual reproduction are the events or processes that takes place before fusion of male female gametes.The two mainpre-fertilisation eventsare gametogenesis and gamete transfer. Gametogenesis is the process in which cells undergo meiosis to form gametes. Microsprogenesis is the process of reduction division of pollen mother cells into pollen grains (male gamete) and megasporogenesis is the process of reduction division of megaspore mother cell into megaspore which further develop into embryo sac (female gametophyte which includes the female gamete egg). Gamete transfer refers to the process of transfer of pollen grain to the stigma. This transfer further facilitates fusion of the gametes in the emryo sac.