If I have the honor to be chose to work for the 29th Olympic Games, I will at first improve my English so that I can talk easily about foreign visitors. Second, I will learn more about history of the Olympics as much as the 2008 Olympic Games. Third, since I was familiar with Beijing, I can help visitors find their ways in the city. Finally, I should be able to tell visitors about our history or culture and show them their great achievements. In short, I will do my best to help making the Games a success.

下列说法正确的是 [     ]

A．同温同压下，H₂ + Cl₂ = 2HCl在光照和点燃条件的△H不同

B．粗铜精炼时，与电源负极相连的是粗铜

C．船底镶嵌锌块，锌作负极，以防船体被腐蚀

D．天然气、沼气和水煤气分别属于化石能源、可再生能源和一级能源