Coombs test is:

Ans. is 'b' i.e., Agglutination test(Ref: Ananthanarayan, 9th/e, p. 109 and 8th/e, p. 108)* Coombs test (antiglobulin test or anti - Rh antibody test) is an agglutination test.* The direct Coombs test is used to detect antibodies that are stuck to the surface of red blood cells. Many diseases and drugs can cause this. These antibodies sometimes destroy red blood cells and cause anemia. Your doctor may order this test if you have signs or symptoms of anemia or jaundice.* The indirect Coombs test looks for free-flowing antibodies against certain red blood cells. It is most often done to determine if you may have a reaction to a blood transfusion.