A.pH4.0 B.pH5.0 C.pH6.0 D.pH7.0
A.5’-TCTA-3’ B.5’-ATCT-3’ C.5’-GCGA-3’ D.3’-TCTA-5’
A.2’,3’-磷酸二酯鍵 B.3’,5’-磷酸二酯鍵 C.糖苷鍵 D.氫鍵