1．“The population ________ issue is severe in USA, but the country has never had more kids, and participation in high school sports has never been higher,” said a professor ________ around 50.
A．aging；aging B．aged；aged
C．aging；aged D．aged；aging
【答案】C
【解析】考查动名词和过去分词。句意：“人口老龄化问题在美国非常严重，但这个国家没有生更多的孩子，高中体育的参与度也没有像现在这样高。”一位大约50岁左右的教授说道。aging表示“老化”，作定语修饰issue，aging issue意为“人口老龄化问题”，aged意为“……岁的”，作后置定语修饰professor。故选C。
