. The transfer of pollen from the anthers of one flower to the stigma of another flower

Best Answer

Explanation- 

Pollination refers to the transfer of pollen from anther to the stigma of a flower. 

Geitonogamy-Transfer of pollen from anthers of one flower to the stigma of another flower of the same plant. 

Xenogamy- Transfer of pollen from anther to the stigma of another flower of a different plant. 

Dichogamy- It is an outbreeding device, to prevent self-pollination here anther, and stigma matures at different times.

1. Protandry-In this anther matures first than the stigma of the same flower, so pollen is transferred to another flower. E.g. Sunflower
2. Protogyny-In this stigma matures first than anther of the same flower. E.G.-Mirabilis jalapa. 

Dicliny- Flowers are unisexual so self-pollination does not take place. It is also an outbreeding device to prevent self-pollination. 

Final Answer- 

So, The correct option is A.