John is an excellent boss ______ he is looked up to by all of hi

John is an excellent boss ______ he is looked up to by all of his employees.
A、but
B、and
C、while
D、or
【正确答案】：B
【题目解析】：约翰是个优秀的老板，他的员工都很尊敬他。本题考查并列句。两个并列的分句可以用and来连接。