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【单选题】
今天的美国人比1965年美国人运动量减少了32%，预计到2030年将减少46%;在中国，与1991年相比，人们运动量减少45%，预计到2030年将减少51%。缺少运动已经成为一个全球性问题。 以下哪项如果为真，最能支持上述观点?A.
其他国家人们的运动量情况和中国、美国大致相同
B.
人们保持健康的方式日益多样化，已不仅局限于运动
C.
中国和美国都是运动量缺乏这一问题较为严重的国家
D.
在运动量方面，中国和美国分别是亚洲和美洲最有代表性的国家
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血红蛋白
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