Triple fusion in angiosperm is the fusion of second sperm with

The correct option is D two polar nuclei
Fertilisation in angiosperms involves two important events - syngamy and triple fusion. In syngamy, one of the sperm released by the pollen tube in the embryo sac fuses with the egg cell and forms a diploid zygote which further develops into embryo. Triple fusion is a characteristic feature in angiosperms where the sperm nucleus fuses with the secondary polar nuclei in the embryo sac.