c
\(\mathrm{O}_{2}^{+}=\mathrm{KK} \sigma 2 \mathrm{s}^{2} \sigma^{*} 2 \mathrm{s}^{2} \sigma 2 \mathrm{pz}^{2}\left(\pi 2 \mathrm{px}^{2}=\pi 2 \mathrm{py}^{2}\right)\left(\pi^{*} 2 \mathrm{px}^{1}\right)\)

\(\mathrm{O}_{2}=\mathrm{KK} \sigma 2 \mathrm{s}^{2} \sigma^{*} 2 \mathrm{s}^{2} \sigma 2 \mathrm{pz}^{2}\left(\pi 2 \mathrm{px}^{2}=\pi 2 \mathrm{py}^{2}\right)\left(\pi^{*} 2 \mathrm{px}^{1}=\pi^{*} 2 \mathrm{py}^{1}\right)\)

\(\mathrm{O}_{2}\) and \(\mathrm{O}_{2}^{+}\) contain unpaired electron in \(\pi^{*}\) ABMO so paramagnetic.