Protects cells against oxidative stress by converting superoxide radicals to hydrogen peroxide (PubMed:16234242). Required for normal brood size (PubMed:18073424). May be involved in regulating mpk-1 phosphorylation downstream of phosphatase ptp-2 during oocyte maturation (PubMed:20380830). 2 H(+) + 2 superoxide = H2O2 + O2 Binds 1 copper ion per subunit. Binds 1 zinc ion per subunit. The insertion of copper which activates the protein requires glutathione. This is independent of copper chaperone for SOD1 (CCS), which activates orthologs. Homodimer. Worms exhibit increased oxidative stress and reduced brood size (PubMed:18073424). RNAi-mediated knockdown suppresses the slow germline development and the delayed egg-production of clk-1 mutants (PubMed:14657502). RNAi-mediated knockdown causes an increase in the number of oocytes with mpk-1 phosphorylation (PubMed:20380830). Belongs to the Cu-Zn superoxide dismutase family.