测量第5腰椎棘突下至耻骨联合上缘中点的距离是（）
A.髂嵴间径
B.出口后矢状径
C.骶耻外径
D.髂棘间径
E.对角径
参考答案：C
(2013·浙江高考)Eye doctors recommend that a child's first eye exam ________ at the age of six months old.
A．was
B．be
C．were
D．is
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