People in all parts of the world are observing "No Tobacco Day". It is the day 1

the World Health Organization (WHO) appeals to people to stop using tobacco products. WHO hopes if people stop smoking cigarettes or 2 tobacco for one day, they will stop permanently.

Health experts have warned for years that smoking can lead to heart disease, cancer and other 3 ．WHO says diseases linked to smoking kill 4 2,500,000 persons each year.

Still, many people find it 5 stopping smoking. One reason is nicotine, a substance found in cigarettes. Nicotine is a drug. Its effects are 6 those of cocaine and heroin.

"No Tobacco Day" is intended for smokers and 7 who earn money from tobacco sales. So businesses are urged to stop selling tobacco products for twenty-four hours. 8 are urged not to carry advertisements for cigarettes.

WHO has approved plans to help reach its 9 of a "smoke-free" world. They urge governments to take action to help 10 make money by growing other crops. They also call for improved public information campaigns about the risks of smoking.

A.whether

B.which

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D.what