狭义光合细菌最本质的特点是（）。
参考答案：狭义PSB最本质的特点是能在厌氧和光照条件下进行不产氧的光合作用
按因果关系排列下列各项，正确的是
①第二次工业革命②生产和资本的高度集中③帝国主义的形成④垄断组织的形成[ ]
A．①②④③
B．②①③④
C．②③①④
D．①②③④
If it is impossible to avoid a hurricane in the Northern Hemisphere，the most favorable place to be when the storm passes is in（）.
A.the dangerous semicircle
B.the eye (center) of the storm
C.that half of the storm lying to the right of the storm's path
D.that half of the storm lying to the left of the storm's path
