20 下列那一種降血壓藥物，長期服用後會有 positive Coombs test（與免疫反應相關，如紅血球溶血反應）之副作用？
(A) Verapamil
(B) Nifedipine
(C) α-Methyldopa
(D) Captopril

cotrimoxazole也有positive coombs test 

The direct Coombs test is used to detect the antibodies or complement proteins that are bound to the surface of red blood cells; a blood sample is taken and the RBCs are washed (removing the patient's own plasma) and then incubated with anti-human globulin (also known as "Coombs reagent"). If this produces agglutinationof RBCs, the direct Coombs test is positive, a visual indication that antibodies (and/or complement proteins) are bound to the surface of red blood cells.

The direct Coombs test is used to test for autoimmune hemolytic anemia; i.e., a condition of a low count of red blood cells(a.k.a. RBCs) caused by immune system lysis or breaking of RBC membranes causing RBC destruction.

The indirect Coombs test is used in prenatal testing of pregnant women and in testing blood prior to a blood transfusion. It detects antibodies against RBCs that are present unbound in the patient's serum. In this case, serum is extracted from the blood sample taken from the patient. Then, the serum is incubated with RBCs of known antigenicity; that is, RBCs with known reference values from other patient blood samples. Finally, anti-human globulin is added. If agglutination occurs, the indirect Coombs test is positive.^[1]