This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Pathology
In the presence of a drug that blocks all effects of norepinephrine and epinephrine on the hea, the autonomic nervous system can 
Select and explain. 
A. Raise the hea rate above its intrinsic rate, B. Lower the hea rate below its intrinsic rate, C. Raise and lower the hea rate above and below its intrinsic rate, D. Neither Praise nor lower the hea rate from its intrinsic rate
B: Lower the hea rate below its intrinsic rate
Answer: B: Lower the hea rate below its intrinsic rate 
Explanation: .