Final answer:
Tolerance refers to the need to use increasing amounts of a substance to achieve the same effects and is distinct from withdrawal symptoms and psychological dependence. Hence, the first option is correct.
Step-by-step explanation:
The need for more and more of the substance to achieve the same effects is known as tolerance. This occurs when a drug user requires greater amounts of a drug to experience effects that were previously achieved with lower doses. Tolerance is a physiological response that can lead to increased drug use, potentially to dangerous levels, and even overdose.
It is differentiated from withdrawal, which involves negative symptoms when drug use is discontinued, and psychological dependence, which is the emotional need for a drug, often used to alleviate psychological distress. Physical dependence is also relevant, as it includes bodily changes that cause withdrawal symptoms when drug use stops.