胆道梗阻性病变时,血清胆汁酸改变正确的是 ( )
A.CA和CDCA浓度减少,但以CDCA为主,CA/CDCA>1B.CA和CDCA浓度增加,但以CA为主,CA/CDCA<1C.CA和CDCA浓度增加,但以CDCA为主,CA/CDCA>1D.CA和CDCA浓度增加,但以CA为主,CA/CDCA>1E.CA和CDCA浓度增加,但以CDCA为主,CA/CDCA<1