属于十二指肠黏膜上皮细胞的是（）。

A.壁细胞

B.G细胞

C.D细胞

D.杯状细胞

E.主细胞

What possible use for beta blockers was NOT discussed in this passage

A．Test anxiety.

B．Z Pain relief.

C．Minor stress.

D．Heart conditions.