Which half-reaction correctly represents a reduction process?

• A. $2{\mathrm{Cl}}^{-}\to {\mathrm{Cl}}_2+2e^{-}$
• B. $Z_{\mathrm{n}}\to Z_{\mathrm{n}}{}^2+2e^{-}$
• C. $C_{\mathrm{u}}{}^2+2e^{-}\to C_{\mathrm{u}}$
• D. $H_2\to 2H^{+}+2e^{-}$

Answer: (C)