Question: Which of the following is true regarding physical drug dependence? Withdrawal symptoms occur upon cessation of drug use. Down-regulation of neurotransmitters or receptors occurs due to long-term drug use. Drug use (and even anticipated drug use) causes activation of the dopaminergic reward pathway in the brain. Drug use is predicated upon the relief of painful emotions. Question Answer Choices A. I and II only B. II and III only C. I, II, and III only D. I, III, and IV only E. II, III, and IV only