I need help. thank you

Plz ! a scientist wants to produce a cow that makes a particular human protein in it’s milk the desired protein causes blood to clot and can be used to treat hemophilia (a blood clotting disorder). which of the following would be best for the scientist to use? a. genetic crosses. b. cloning. c. selective breeding. d. genetic engineering.

What causes darkening of the skin as melanin production increases

If a grape were placed in a hypertonic solution what would happen and why?