税收制度的基本要素包括（）。

A.纳税人

B.税率

C.征税对象

D.纳税期限

E.纳税环节

—How dangerous it was!

—Yes, but for the passer-by’s quick action, the girl ________.

A．was drowned

B．could have been drowned

C．had drowned

D．should be drowned