This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Other topics and Adverse effects, Subject name: Anatomy
Which of the following drugs act through heptahelical receptors 
Select and explain. 
A. Insulin, B. Estrogen, C. Local anaesthesia, D. Salbutamol
D: Salbutamol
Answer: D: Salbutamol 
Explanation: Ref-KDT 6/e p45 GPCRs are heptahelical or serpentine receptor.salbutamol acts thrithr beta2 receptor which are GPCRs