Answer :
Cocaine, amphetamines, caffeine, nicotine, and MDMA (ecstasy) have in common that they all increase the activity of the nervous system (Option a).
What are stimulant drugs?
The expression stimulant drugs is used in biology and medicine to describe chemical substances that speed up the velocity in which messages are transmitted between nerve cells, which is common to caffeine, nicotine cocaine and ecstasy.
Therefore, with this data, we can see that stimulant drugs are able to increase the velocity in which messages are transmitted in the nervous system.
Learn more about stimulant drugs here:
https://brainly.com/question/14844601
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