Mike, whose ambition is to become a network engineer, was always ______from other boys by his programming ability.   

A．prevented

B．separated

C．benefited

D．distinguished

信用证规定“Certificate of origin G. S. P. Form A in duplicate”，根据要求，该产地证的签发机构是：（）

A.贸促会（商会）

B.出境地海关

C.生产地公证处

D.出入境检验检疫局