Mrs. Liu is kind and always _____ her help to others. [ ]

A. shares

B. receives

C. makes

D. offers

原发性甲状旁腺功能亢进症最常见的病因是（）。

A.甲状旁腺单个腺瘤

B.甲状旁腺多个腺瘤

C.甲状旁腺单个腺体增生

D.甲状旁腺多个腺体增生

E.甲状旁腺腺癌