A:c(OH﹣)﹣c(H+)=c(CH3COOH)
B:c(Na+)>c(CH3COO﹣)>c(OH﹣)>c(H+)
C:c(Na+)﹣c(CH3COO﹣)=c(OH﹣)﹣c(H+)
D:c(Na+)=c(CH3COOH)+c(OH﹣)
观察细菌的形态可以借助于( )