Double fertilization occurs in Angiosperm. In this fertilization, one male gamete enters to the ovule and fuse with the egg cell result into the formation of diploid zygote while another male gamete fuse with the polar nuclei (2n) or secondary nucleus present in the center results into the formation of primary endosperm nucleus(3n) and that will be triploid in nature. Endosperm will form from the primary endosperm nucleus. They provide nourishment to the developing embryo. So the correct answer is B. Embryo will be able to survive when endosperm grows faster. Synergids guide the pollen tube and it degenerates after fertilization.