Which of the following are classified as stimulants?

Stimulants are substances that increase activity in the central nervous system, leading to heightened alertness, attention, and energy. Cocaine is a well-known stimulant that works by increasing levels of dopamine, a neurotransmitter associated with pleasure and reward, in the brain. It results in feelings of euphoria, increased heart rate, and heightened energy levels.

In contrast, narcotics (often opiates) are primarily used for pain relief and can depress the central nervous system, leading to sedation rather than stimulation. Anabolic steroids are synthetic variations of testosterone and are primarily used for muscle growth and performance enhancement, but they do not fit into the stimulant category. Depressants, as the name suggests, slow down brain activity and can induce relaxation, sleepiness, or reduced anxiety. Therefore, only cocaine is classified as a stimulant among the given options.