室内空气污染的CO2主要来自（）
A．装饰材料
B．建筑材料
C．吸烟
D．燃料燃烧
E．烹调油烟
参考答案：D
Looking at the beautiful vase , he could not help saying, “_____”.
A．Nothing could be more remarkable
B．The more , the better
C．Anything is possible
D．Something is better than nothing
