Which of the following is "file lawsuit"?

• 法律

• 律师

• 事务所

• 打官司

需要 means:

• help

• if

• need

• viewpoint

事务所 means：

• firm/agency

• urgency

• toilet

• place

熟悉 means：

• acquaintance

• be familiar with

• inquiry indirectly

• over heard

公务员 means：

• lawyer

• civil servant

• manager

• movie director

国营公司 means：

• state-owned company

• private-owned company

• to run business

• develop economy

老一代 means:

• generation gap

• older generation

• younger generation

• next generation

Which of the followings is "to agree"?

• 满意

• 意义

• 同意

• 分配

平安 means：

• half an hour

• Good night

• peaceful and safe

• equality

Which of the followings is 挑战？

• future

• competition

• challenge

• reply on