Soybeans Are a Self-Compatible Species, in Which the Pollen Matures

Soybeans are a self-compatible species, in which the pollen matures and is released from the anthers even before the flower opens. As a result, most ovules are fertilized by pollen from the same flower. In animals, mating between closely related individuals results in a significant loss in vigor (in-breeding depression) . Why is this NOT a significant problem in plants?

A) The dominant angiosperm generation is diploid, which prevents recessive genes from being expressed.
B) Natural selection during the haploid gametophyte generation tends to eliminate recessive genes that have deleterious effects on the growth and development of the gametophyte.
C) In seed plants, the sperm does not have to swim to reach the female gamete (egg) , but is instead carried there by the pollen tube.
D) Double fertilization makes it impossible for the diploid offspring to be homozygous at any loci.