What is the purpose of a blood typing test?

A blood typing test serves the important function of determining an individual's blood group, which is crucial for ensuring transfusions are safe and effective. Blood groups are classified based on specific antigens present on the surface of red blood cells. The most recognized system for blood typing is the ABO system, which categorizes blood into four main groups: A, B, AB, and O. Additionally, the Rh factor is assessed to determine if the blood type is positive or negative (e.g., A+, O-).

Knowing a person's blood group and Rh status is essential prior to blood transfusions because incompatible blood can lead to serious and potentially life-threatening reactions. For instance, if a person with type A blood receives type B blood, their immune system may recognize the foreign antigens and mount an immune response, which can result in hemolysis, organ failure, or shock.

In contrast, the other choices relate to different medical evaluations: assessing glucose levels tracks diabetes management, evaluating kidney function monitors renal health, and determining cholesterol levels helps in assessing cardiovascular risk. However, none of these functions align with the primary purpose of a blood typing test, which revolves specifically around blood group compatibility.