The "just say no" campaign was an effort to
discourage drug use
end corruption in government
prevent risky financial practices
end the arms race with the soviets

The answer to the question stated above is the first choice,discourage drug use.

The "Just Say No" campaign was an effort to discourage drug use. 
"Just Say No" is an advertising campaign and is a part of the United State's war against illegal use of drugs (WAR ON DRUGS). This was created and led by President Ronald Reagan's wife, First Lady Nancy Reagan during his presidency.