In the flowering period of maize, if there is more rain and less rain, it will often cause maize yield reduction. What is the reason?

Hello, let me explain something to you. Corn is a monocotyledonous plant in Gramineae. After flowering, it is wind-borne Corn is bisexual. The male flowers are at the top of the whole plant. As soon as the wind blows, pollen is scattered on the female flowers growing in the middle of the sunken plants, thus completing the fertilization process and stimulating ovarian development. However, after the heavy rain, some pollen was washed away by the rain, and the pollen could not reach the stigma of the female flower smoothly, or even if it could, it would be greatly reduced, resulting in reduced production. After my explanation, the answer is obvious, choose D.