Why Is Rice Shared in a Japanese Wedding

Why is rice shared in a Japanese wedding?

A) As a form of commensality it helps reinforce the creation of kin ties.
B) Rice represents peace in the Japanese culture, so eating it at a wedding ensures a peaceful marriage.
C) Rice isn't eaten, it is thrown (to ensure fertility) .
D) It ensures the quick birth of a healthy child.
E) Actually rice is not shared at all.