Faced with a bill for ＄10,000, _____. [ ]

A. John has taken an extra job

B. the boss has given john an extra job

C. an extra job has been taken

D. an extra job has been given to John

一个用户可以有多个PDP上下文，所有PDP上下文都与该用户唯一的一个MM上下文相关联。