Answer:
The correct answer is A
Step-by-step explanation:
Myocardial infarction means there isn't an adequate amount of oxygen getting into cardiac muscles , due to the blood flow getting blocked , which in the end might cause a cardiogenic shock.
The rest of the options wouldn't make sense , because , an increased cardiac output , can increase the blood pressure on the vessels , which in response increases the blood flow.
An increased sympathetic outflow to the heart leads to the heart rate increasing , which increases in response the cardiac output ( Cardiac output = stroke volume x heart rate) , which leads to the previous point mentioned.
Parasympathetic antagonists are actually used to treat myocardial infarction (it decreases the heart rate, which prolongs the duration of diastole, and thereby supports diastolic filling and coronary blood flow) which is the main cause of cardiogenic shock. So, it wouldn't be the correct answer either.
This leaves out the first option as the only correct answer.