Altogether how many people were injured during the violence（）

A. It explains why you need extra time when you visit Arab countries.
B. It discusses how to be polite when doing business in the Arab world.
C. It implies why Arab officials and executives are so busy.
D. It tells us how difficult it is to do business with Arabs.

A. Working at the office is safer than staying at home.
B. Travelling to work on public transport is safer than working at the office.
C. Staying at home is safer than working in the chemical industry.
D. Working in the chemical industry is safer than travelling by air.