Final answer:
Option (D), Tolerance is the physiological process where more of a drug is required to achieve the same effect as before.
Step-by-step explanation:
The reduction in the body's response to a drug, which may accompany continual drug use, is called tolerance. This tolerance occurs when a user requires increasingly larger doses of a drug to achieve the same effect that was initially experienced with smaller doses.
It is a physiological process that can lead to more dangerous levels of consumption, potentially resulting in an overdose and death. Addiction refers to the compulsive use of a drug despite the negative consequences, while dependence may be physical or psychological, where cessation of drug use produces withdrawal symptoms.