Which one of the following is an example of Heterogeneous catalysis?

• A. \(2S{O_{2\left( g \right)}} + {O_{2\left( g \right)}}\mathop \to \limits^{N{O_{\left( g \right)}}} 2S{O_{3\left( g \right)}}\)
• B. \(C{H_3}COOC{H_{3\left( 1 \right)}}\mathop \to \limits^{HV{I_{\left( 1 \right)}}} C{H_3}COO{H_{\left( {aq} \right)}}\)
• C. \({N_{2\left( g \right)}} + 3{H_{2\left( g \right)}}\mathop \to \limits^{F{e_{\left( s \right)}}} 2N{H_{3\left( g \right)}}\)
• D. \({C_{12}}{H_{22}}{O_{11\left( {aq} \right)}} + {H_2}{O_{\left( 1 \right)}}\mathop \to \limits^{{H_2}S{O_{4\left( 1 \right)}}} {C_6}{H_{12}}{O_{6\left( {aq} \right)}} + {C_6}{H_{12}}{O_{6\left( {aq} \right)}}\)