直接从各种污染源排放到大气中的有害物质称为二次污染物。

A、二氧化硫

B、一氧化碳

C、过氧乙酰基硝酸酯

D、一氧化氮

我国各地的雾霾，从总的方面来说是各种来源污染排放物经过一系列的化学和物理过程的产物，这里既有一次排放，还有二次化学转化和物理过程。从南到北情况十分复杂，当下的普遍情况既不同于当年伦敦的情况，也不同于洛杉矶的情况，曾有学者讲北京的情况属于“伦敦型”和“洛杉矶型”的复合型，实际上事情绝非是绝非是一个“复合型”可以概括。还让人担心的是：眼下从上到下、各省各地，从官员到普通老百姓都认为燃煤是问题的根子，似乎解决了城市燃气化以后，问题就可以大大解决了，其实我们的一次排放物或者说二次过程的出发物质决不只是一个二氧化硫，或者说再加上一个氮氧化合物那么简单。 这段文字概括最恰当的是

A.雾霾形成的原因复杂

B.雾霾形成的主要特点

C.雾霾类型具有多样性

D.雾霾危害具有普遍性

A、A. With the rapid development of industrialization and urbanization of China's economy, haze appears in a large number of cities and their surrounding areas, which is considered to be one of the major realistic problems facing the sustainable development of China's social economy.

B、B. Along with the stage of China's economy entering the rapid development of industrialization and urbanization, the smog phenomenon has appeared in many cities in China and its surrounding areas, and is considered to be one of the major practical problems facing the sustainable development of China's social economy.

C、C. As China has seen rapid industrialization and urbanization, smog prevails in a large number of Chinese cities and their surrounding areas, and is considered one of the major problems threatening China’s social and economic sustainability.

D、D. With China's economy entering the stage of rapid industrialization and urbanization, smog phenomenon appears in a large number of cities and their surrounding areas in China. It is considered to be one of the major practical problems facing China's sustainable social and economic development.