It was with great delight that I read in your February _____ the letter to the Editor written by Prof. Johnson.

A．issue

B．printing

C．magazine

D．copy

境外的勘察设计单位及其在中国境内的办事机构，承接在中国境内建设项目的勘察设计业务时必须( )。

A．单独承接

B．与中方勘察单位合作承接

C．与港澳台商合作承接

D．与外资勘察单位合作承接