Transfers substances to the brain faster than when a drug is injected or swallowed.

a. smoking
b. eating
c. inhalation
d. snorting

A. Smoking

Explanation:

Nicotine modifies the functioning of the brain, specifically acts on the nicotine cholinergic receptors that are part of the reward circuit, releasing dopamine, which is the neurotransmitter of motivation and reward. In addition, it does so very quickly, between only 10 to 15 seconds it is transported from the lungs to its receptors through the bloodstream. In fact, the fastest way to carry a substance to the brain is to smoke it, which generates much stronger effects of conditioned reinforcement. Tobacco is the drug that has the highest probability of dependence just by trying it once (32%).

Tobacco addiction is due, as we have already said, to the release of dopamine, specifically in the cerebral zone of the ventral striatum (nucleus accumbens), the so-called mesolimbic dopamine pathway, the reinforcement pathway and the brain's reward.

your answer will be c. sorry if im wrong: )