下列反应<em>不属于</em>分解反应的是（）。<br>A:H<sub>2</sub>CO<sub>3<img src="/Image1/9a/9a3da3d371f1c7ff2a892c911c1018e6.jpg" /></sub>CO<sub>2</sub>↑+H<sub>2</sub>O<br>B:2HgO<img src="/Image1/78/781390d6d99f9990b1577e78fc94ccbd.jpg" />2Hg+O<sub>2</sub>↑<br>C:2H<sub>2</sub>O<sub>2</sub><img src="/Image1/22/223aabaf950ff4ceeb36f65193406d59.jpg" />2HO<sub>2</sub>+O<sub>2</sub>↑<br>D:Mg+CuO<img src="/Image1/78/781390d6d99f9990b1577e78fc94ccbd.jpg" />Cu+MgO