题目

阅读下面短文，从短文后各题所给的A、B、C和D四个选项中，选出可填入空白处的最佳选项。Daniel Hernandezalways knew he wanted to help people. He felt 1 by the good deeds that responsible lawmakerscan do, so in his junior year at the University of Arizona, he declared a majorin 2 and began volunteering in political campaigns.One of his heroes was his local congresswoman, Gabrielle Gi ffords. He was 3 when he was picked for an internship (实习) with her, and he gladly 4 a part-time sales job for the chance to workon her team. So 5 was he that he started work f某学生用量筒取液体时，使视线同溶液凹液面的最低处保持水平，读数为18毫升；倒出部分液体后，俯视凹液面的最低处，读数为12毫升，则该学生实际倒出的液体体积为（　　）     A、肯定大于6毫升       B、肯定小于6毫升     C、肯定等于6毫升       D、可能大于也可能小于6毫升