Left-hand panel: all VMC stars with a detection in J and K_s, redder than (J − K_s) = 1.5 mag and above the line K_s = 3 ⋅ (J − K_s)+10 mag. The second-order polynomial is a fit to the red sequence of AGB stars, shifted downward by two magnitudes for comparison purposes (see text). Objects that are (probable) stars are indicated in black, and (probable) galaxies are indicated in red. Objects classified differently are indicated in blue. Right-hand panel: synthetic photometry from GS18 for 29 SMC and 133 LMC O- (open circles) and C-rich (filled circles) AGB stars with pulsation periods longer than 450 days. The pulsation periods of the objects marked in red are derived from K/K_s or WISE-band data, and the black points are derived from optical data (OGLE, EROS, and MACHO).