The correct option is D gonadotropins
Infertility of local breeds can be overcome by use of gonadotropins. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) are called gonadotropins because they stimulate the gonads - in males, the testes, and in females, the ovaries. FSH - Follicle Stimulating Hormone is injected into the female animal, which causes multiple eggs to be released by the ovaries. Then, semen is deposited in the female through artificial insemination and once fertilised, the embryos are recovered non-surgically at the 8 - 32 cells stage. The multiple embryos thus produced are transferred to surrogate mothers.