8. a special danger of drug use is that you a. can never know when it's unsafe to drive b. must commit a crime in order to obtain drugs c. may not realize you are impaired d. a and c

The special danger a drug imposes is D. the driver may not know if it is safe to drive and the driver also not know if he/she is impaired.

The traffic rules always warn against drunk driving or driving while intoxicated. When someone is influenced by drugs, rational thinking is weak and the ability to make a good decision is also reduced hence one may not have the ability to judge whether it is safe or unsafe to drive. Driving under the influence of drugs may not cause accidents at all times but it endangers the lives of the driver and other motorists.  

Prolonged use of drugs causes addiction and other health problems which may be hard to treat. People addicted to drugs may have used drugs for fun, peer pressure or to relieve stress. With time the behavior becomes a norm which leads to addiction.

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