Recently genes have been indentified in angiosperms that are

Recently, genes have been indentified in angiosperms that are important in preventing pollen from germinating or growing into the stigma. The locus where the genes are found has been termed the

Solution

D) Sterility locus.

The best studied mechanisms of SL act by inhibiting the germination of pollen on stigma, or the elongation of pollen tube in the styles. these mechanisms based on protein-protein interaction, and the best undersood mechanisms are controlled by a single locus termed S, which has different allels in the species population.