题目7单选题
Which of the following statements about CO-bound hemoglobin (COHb) is wrongA. In an average, healthy individual, 1% or less of the total hemoglobin is complexed as COHbB. Since CO is a product of tobacco smoke, many smokers have COHb levels in the range of 3% to 8% of total hemoglobin, and the levels can rise to 15% for chain-smokersC. COHb levels equilibrate at 50% in people who breathe air containing 570 ppm of CO for several hoursD. Because of their higher base levels of COHb, smokers exposed to a source of CO often develop symptoms slower than nonsmokers