Answer:
A. All of these choices are correct.
Step-by-step explanation:
In pharmacology , drugs play different roles from simple to complex.
as is the above mentioned question drugs can facilitate the transmission of information from one neuron to another so option B is correct.
While the drugs / chemicals can inhibit the transmission of information from neuron to another so option C is also correct.
And the drugs can also be used to cure a whole variety of clinical disorders by playing a role at the synaptic level.
Hence option A All of these choices are correct is the right answer.