Answer:
d.
"Adaptation results in an increased sensitivity to side effects over time."
Explanation:
It should be understood that, with the adaptation of the central nervous system to prolonged exposure to CNS drugs, many adverse effects will diminish and therapeutic effects will remain.
Note that, adaptation helps in explaining how tolerance and physical dependence occur, as the brain adapts to the presence of the drug. Therapeutic effects can take several weeks to manifest, because they appear to work by initiating adaptive changes in the brain.
In summary, therapeutic effect can be described as the favorable response or outcome after a kind of treatment.
