Azimuthal correlation function of D mesons with charged particles with different parton-level contributions from PYTHIA8 (left panel) and POWHEG+PYTHIA8 simulations (right panel) in pp collisions at $\s = 13$ \TeV, for $0.3 <\ptass< 1$ \GeVc and $3 <\ptD< 5$ \GeVc.