The correct answer is C. Landsteiner and Weiner.
Karl Landsteiner and Alexander Weiner discovered the Rh factor in 1940. They found that the blood of some people contained a substance that caused antibodies to form in the blood of others. This substance was later called the Rh factor.
The Rh factor is a protein that is found on the surface of red blood cells. It is inherited from parents. People who have the Rh factor are Rh-positive, and people who do not have the Rh factor are Rh-negative.
The Rh factor is important because it can cause problems during pregnancy and childbirth. If an Rh-negative woman is pregnant with an Rh-positive baby, her body may produce antibodies against the baby’s blood cells. This can cause a condition called hemolytic disease of the newborn, which can be fatal to the baby.
There is a blood test that can determine a person’s Rh factor. This test is usually done before a person gets pregnant or has a blood transfusion.