The DAC model consists of two interaction regions with strong quantum interference. We first study the low-energy scattering and consider a representative case with the initial momentum k0 = 16 au. The population and coherence distributions at and). Both FSSH-wf and BCSH-wf demonstrate notable deviations from the exact quantum reference because the gradual separation of WPs on different PESs induces slow decoherence and is not accurately captured by the wavefunction. In contrast, BCSH-as still yields nearly the correct results for population distributions on both lower and upper PESs. This further confirms that occupation of active states can provide more reliable population compared to that by wavefunctions.