Any one? Please help me :(

Which of these statements are true about scientific theories and hypothesis

How did the discovery of the rhesus factor affect society? o more patients died from having a transfusion with the wrong rhesus factor 0 new treatments during pregnancy could prevent harm to the developing child. o less donated blood could be used in the treatment of patients. the number of blood types was reduced by half

Explain how the number of similarities between the embryos from early stage to late stage is used as evidence of a common ancestry