喉鳞癌最常见的发病因素是()。
A.先天遗传
B.吸烟与饮酒
C.环境污染
D.病毒感染
E.不良饮食习惯
参考答案:B
解析:喉鳞癌最常见的发病因素是吸烟与饮酒。
When the environmentally friendly cars came onto the market, many people were eager to buy them ________ the price.
A.wherever
B.however
C.whichever
D.whatever
防护林都包括什么林种?