It was only when I reread his poems recently _____ I began to appreciate their beauty. [ ]

A. until

B. that

C. then

D. so

控件的类型可以分为( )。

A．结合型、对象型、非结合型

B．对象型、非结合型、计算型

C．对象型、结合型、计算型

D．结合型、非结合型、计算型