Describe the effect of drug abuse on the spread of HIV

Drug abuse and addiction have been inextricably linked with HIV/AIDS since the beginning of the epidemic. While intravenous drug use is well known in this regard, less recognized is the role that drug abuse plays more generally in the spread of HIV by increasing the likelihood of high-risk sex with infected partners.3 The intoxicating effects of many drugs can alter judgment and inhibition and lead people to engage in impulsive and unsafe behaviors. Also, people who are abusing or addicted to drugs may engage in sexually risky behaviors to obtain drugs or money for drugs. Nearly one-quarter of AIDS cases stem from intravenous drug use, and one in four people living with HIV/AIDS in the period of 2005–2009 reported use of alcohol or drugs to an extent that required treatment.

answer; /// i believe the correct answer is (thrombocytopenia); (a)

it is either c or d and i know for sure it is not a or b