$6 \mathrm{H}_{2} \mathrm{~S}+6 \mathrm{CO}_{2} \stackrel{\text { light }}{\longrightarrow} 6 \mathrm{~S}^{0}+$

$6 \mathrm{H}_{2} \mathrm{~S}+6 \mathrm{CO}_{2} \stackrel{\text { light }}{\longrightarrow} 6 \mathrm{~S}^{0}+$ glucose
-Sludge digestion

A) Takes place under aerobic conditions.
B) Takes place under anaerobic conditions.
C) The amount of oxygen doesn't make any difference.