The correct answer is :

Option A : Geitonogamy

Explanation :

Geitonogamy refers to the transfer of pollen from the anther of one flower to the stigma of another flower on the same plant. While this process involves pollination between different flowers, because it occurs on the same plant, it does not increase genetic diversity.

Here's a quick overview of the other terms :

• Xenogamy refers to the transfer of pollen grains from the anther of a flower to the stigma of a flower on a different plant. This is cross-pollination and promotes genetic diversity.
• Autogamy refers to the transfer of pollen from the anther to the stigma of the same flower. This is self-pollination.
• Cleistogamy refers to a type of automatic self-pollination where the flowers do not open and are therefore self-pollinated before they open.