If \(x\) is a positive real number different from 1 such that \(\log _{a} x, \log _{b} x, \log _{c} x\) are in A.P., then
(A) \(b=\frac{a+c}{2}\)
(B) \(b=\sqrt{a c}\)
(C) \(\mathrm{c}^{2}=(\mathrm{ac})^{\log \mathrm{b} \mathrm{b}}\)
(D) None of (A), (B), (C) are correct