单选题
Which of the following best describes the author's attitude toward the increasing amount of carbon dioxide in the atmosphere and its consequences?
【正确答案】
A
【答案解析】本文作者用数字计算客观陈述了二氧化碳的现状，从第二段Today，however， the potential problem is too much carbon dioxide等处可以看出作者对其增加是充满忧虑的。