Measurements of azimuthal-correlation function baseline height in \pp collisions at $\s = 5.02$ \TeV, compared to predictions by the PYTHIA, POWHEG+PYTHIA6, POWHEG LO+PYTHIA6, HERWIG, and EPOS 3 event generators with various configurations in the top row (see text for details). The ratios of baselines with respect to predictions by POWHEG+PYTHIA6 are shown in the bottom row. Results are presented as a function of the D-meson $\pt$, for $\ptass > 0.3$~\GeVc, $0.3 < \ptass < 1$~\GeVc, $1 < \ptass < 2$~\GeVc, and $2 < \ptass < 3$~\GeVc (from left to right). Statistical and systematic uncertainties are shown as vertical error bars and boxes, respectively.