This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Nervous System, Subject name: Physiology
Consider the following statementI Experimental hypertension can be produced to stimulating sinoaortic nerveII Sino-aortic nerve normally stimulates vasomotor centre Of these statements 
Select and explain. 
A. I is true but II is false, B. Both I and II are true, C. I is false but II are true, D. Both I and II are false
A: I is true but II is false
Answer: A: I is true but II is false 
Explanation: (A) I is true but II is false Stimulation of the noradrenergic nerves to the intestine inhibits contractions in vivo.> Norepinephrine exerts both a & ft actions on the muscle> The b action, reduced muscle tension in response to excitation, is mediated via cyclic AMP and is probably due to increase: tracellular binding of Ca2+.> The a action, which is also inhibition of contraction, is associated with increased Ca2+ efflux from the muscle cells.