. Since last year, the global economic slowdown ________ in many countries. It is expected that the world economy will not recover until the end of 2010.

A．is spreading

B．spread

C．had spread

D．has been spreading

（）是指人们在有目的地探索和改造现实世界的一切社会性客观物质活动过程中所表现出来的能力和素质。