What test is used to identify blood types What principle is utilized to make the test?

The test used to identify blood types is the ABO blood typing test, which involves mixing a sample of blood with specific antibodies that react with the A and B antigens present on the surface of red blood cells. The principle utilized in this test is agglutination, where the binding of antibodies to their corresponding antigens causes clumping of the blood cells, indicating the presence of specific blood types. For example, if anti-A antibodies cause agglutination, the blood type is A.