JF is an 80-year-old male diabetic who is a very poor historian. His family escorts him to your emergency room because he complained of an episode of acute dyspnea 8 days ago. His ECG is now normal,...

JF is an 80-year-old male diabetic who is a very poor historian. His family escorts him to your emergency room because he complained of an episode of acute dyspnea 8 days ago. His ECG is now normal, but you are concerned that JF may have had an NSTEMI-induced CHF episode 8 days ago. Which biochemical test would be the most helpful to determine whether or not he had an infarct 8 days ago?

A. CK

B. SGOT

C. Troponin I

D. LDH

E. Myoglobin