Sentence:  The only thing working against the poor <WSD>Drug</WSD> Abuse Resistance Officer is high-school students. ... He'd offer his simple lesson: <WSD>Drugs</WSD> are bad, people who use <WSD>drugs</WSD> are bad, and abstinence is the only answer. 
Meaning of the word marked with <WSD> tags:  A psychoactive substance, especially one which is illegal and addictive, ingested for recreational use, such as cocaine.