  The moments and moment products of conserved charges are believed to be
sensitive to critical fluctuations, which have been adopted in determining the
QCD critical point. Using a dynamical multiphase transport model, we reproduce
the centrality and energy dependences of moments and moment products of
net-charge multiplicity distributions in Au+Au collisions measured by the Beam
Energy Scan program at the RHIC. No non-monotonic energy dependence is
observed. We infer that the moment products develop during the dynamical
evolution of heavy-ion collisions. The observed difference based on the
expectation of the Poisson baseline indicates a positive two-particle
correlation between positively and negatively charged particles, which can
arise from different dynamical processes at different stages. Therefore, to
adopt moments and moment products of net-charge multiplicity distributions in
determining the QCD critical point of relativistic heavy-ion collisions, it is
essential to take the dynamical evolution.
