This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: C.V.S, Subject name: Medicine
[{'content': 'The central venous pressure (CVP) is slow in- \nSelect and explain. \nA. Pericardial effusion, B. Massive pulmonary embolism, C. Acute left ventricular failure, D. Tension pneumothorax', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Factors Increasing Central Venous Pressure A decrease in cardiac output either due to decreased hea rate or stroke volume (e.g., in ventricular failure) results in blood backing up into the venous circulation (increased venous volume) as less blood is pumped into the aerial circulation. Ref Davidson 23rd edition pg 453', 'role': 'assistant'}]