Answer: A
I21 is correct as the diagnosis is made as acute myocardial infarction and this code is used for this condition.
Option B is not correct because E10.65 codes for type I diabetes mellitus with hyperglycemia. Here, the patient has a history of type II diabetes mellitus but this is not the primary diagnosis.
Option C is not correct because E11.65 codes for type II DM with hyperglycemia. Though, the patient has a history of type II diabetes mellitus but this is not the primary diagnosis here.
Option D is not correct I20 is used to code angina pectoris. Here, the diagnosis is myocardial infarction.