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 person comes into your ER room with a very weak pulse after a suffering a heart attack. You suspect: 
Select and explain. 
A. The weak pulse has nothing to do with shock or the heart attack, so send him home., B. A late stage (decompensated) shock, the least life-threatening stage of shock., C. A very early stage (compensated) shock, the most life-threatening stage of shock., D. A late stage (decompensated) shock, the most life-threatening stage of shock
D: A late stage (decompensated) shock, the most life-threatening stage of shock
Answer: D: A late stage (decompensated) shock, the most life-threatening stage of shock 
Explanation: D:  A very weak pulse shows that the heart is slowly ceasing to function as a result of pumping too hard.
A: The patient should not be sent home; close observation is necessary.
B: This stage is a life-threatening stage as the heart could tire itself out and stop functioning.
C: An early stage of shock shows a rapid, bounding pulse.