Answer:
The correct answer is option (b) "addition of a drug that prevents the α subunit from exchanging GDP for GTP".
Explanation:
The G protein is a name given to a family of proteins that act as a switch in diverse cellular processes, transmitting signals from outside to inside of the cells. When a G protein receptor is activated by a neurotransmitter such as dopamine, the alpha subunit exchanges its GDP for a GTP and disassociates G-protein itself. An addition of a drug that prevents this action would prevent G protein disassociation, which would enhance the effect of stimulating G protein that acetylcholine does.
The answer to your outstanding question is 3
