The correct option is C a male gamete and two polar nuclei
After the pollen tube releases the two male gametes into the cytoplasm of the synergid, one male gamete goes onto fuse with the female gamete i.e. the egg cell and the other male gamete goes on to fuse with the two polar nuclei.
This fusion of a male gamete with the two polar nuclei results in the formation of the primary endosperm nucleus (PEN). PEN develops into endosperm.