Over the past couple of years, a variety of talent shows______on TV channels across the nation, from Super Girls to Happy Boys.

A．appeared

B．had appeared

C．have appeared

D．were appearing

伴有房室传导阻滞的心绞痛患者宜选用的钙拮抗药是（）

A.地尔硫卓

B.维拉帕米

C.硝苯地平

D.氨氯地平

E.米贝地尔