Which one of the following molecules is expected to exhibit diamagnetic behaviour?

Based on Molecular Orbital Theory:${\text{N}}_2$ (14 electrons): $\sigma 1s^2{\sigma }^{\ast }1s^2\sigma 2s^2{\sigma }^{\ast }2s^2(\pi 2p_x^2=\pi 2p_y^2)\sigma 2p_z^2$. All electrons are paired. Diamagnetic.${\text{O}}_2$ (16 electrons): Has 2 unpaired electrons in ${\pi }^{\ast }$ orbitals. Paramagnetic.${\text{S}}_2$ (similar to ${\text{O}}_2$): Has 2 unpaired electrons. Paramagnetic.${\text{C}}_2$ (12 electrons): $\sigma 1s^2{\sigma }^{\ast }1s^2\sigma 2s^2{\sigma }^{\ast }2s^2(\pi 2p_x^2=\pi 2p_y^2)$. All electrons are paired. Diamagnetic.Note: Both ${\text{N}}_2$ and ${\text{C}}_2$ are diamagnetic. In the original 2013 paper, both options were valid.