The catalogue website can offer the most useful gifts to ____ poor and bring hope for

a better future to a community in____ need.

A．a ; the

B．the ; a

C．the; \

D．a; a

DSA的常用成像方式是（）

A.时间减影

B.能量减影

C.混合减影

D.体层减影

E.K-缘减影