A. G proteins bind to hormones on the cell surface
B. All the three subunits alpha, beta and gamma should bind each other for G protein to act
C. G Proteins act as inhibitory and excitatory because of difference in alpha subunit
D. G protein is bound to GTP in resting state
✅ The correct answer is option C. G Proteins act as inhibitory and excitatory because of difference in alpha subunit.