This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Medicine
A patient with M of 4 yrs duration presents with dizziness and HR 52/min, probable cause isa) Hypoglycaemiab) Inferior wall MIc) Sick-sinus syndromed) Autonomic dysfunction 
Select and explain. 
A. bcd, B. acd, C. ac, D. bd
A: bcd
Answer: A: bcd 
Explanation: None