Barack Obama delivered a speech to 500 local youths during his visit to China, many of     were from Fudan University and Tongji University.

A．them

B．whom

C．which

D．those

中组发[1982]13号文件规定，建国前参加革命工作未担任司局（地专）级职务的行政十四级以上老干部离休后，一般可享受什么级的政治、生活待遇？