Top: m _F814W vs. C _{F606W,F814W,F322W2} pseudo-CMD for stars in field B. The inset shows the Δ _{CF606W,F814W,F322W2} vs. Δ_F606W,F814W ChM for MS stars with 21.5 < m _F814W < 24.0 mag, and the corresponding Δ _{CF606W,F814W,F322W2} kernel-density distribution. Bottom: NIRSpec spectra for the two stars marked with large dots in the pseudo-CMD and in the ChM (left). Two simulated spectra with [O/Fe] = +0.3 (red) and [O/Fe] = −0.1 (blue) are superimposed on the observed spectra in the bottom-right panel.