髌骨软化的病变部位为（）
A.骶髂关节
B.髌骨关节软骨
C.软骨下骨
D.十字韧带
E.关节囊
参考答案：B
The limits of a person's intelligence, generally speaking, are fixed at birth, but ________ he reaches these
limits will depend on his environment. [ ]
A. where
B. whether
C. that
D. why
曲线半径为650m的到发线，圆曲线正矢连续差经常保养容许偏差为（）。
A.6mm
B.8mm
C.10mm
D.12mm
