第19题: [单项选择]Two thirds of the U. S. basketball players are black, and the number would be greater()the continuing practice of picking white bench warmers for the sake of balance. A. was it not because of B. had it not been for C. were it not for D. would it not have been for 参考答案:C
第30题: [单项选择]吮拇指习惯易造成()。 A. 前牙反 B. 深覆盖 C. 前牙梭形开 D. 前牙圆形开 E. 以上都不是 参考答案:D 答案解析:不良口腔习惯是造成错畸形的常见原因。例如咬上唇习惯易形成前牙反;咬下唇习惯会引起前牙深覆盖、下颌后缩;伸舌习惯常使前牙梭形开;咬物或咬小指会形成局部小开;吮拇指习惯则易形成前牙圆形开。故本题选D。
第31题: [单项选择]引起尖锐湿疣的病原菌是()。 A. BV B. HPV C. PCR D. VVC E. LPD 参考答案:B