**Core Concept**
Myocardial infarction (MI) diagnosis involves assessing cardiac biomarkers like creatine kinase (CK) and its isoenzyme, CK-MB. Elevated levels of these enzymes in the blood are indicative of cardiac muscle damage. However, their levels may not always peak within the first 2 days post-MI.

**Why the Correct Answer is Right**
The normal levels of CK and CK-MB after 2 days of chest pain suggest that the patient may not have had a recent MI. This is because CK-MB levels typically peak within 24-48 hours after an MI and then return to baseline. If the levels are normal after 2 days, it may indicate that the chest pain was caused by a non-cardiac origin. This is consistent with the concept of "normal" CK-MB levels being a useful but not definitive indicator of the absence of MI.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is not provided.
**Option B:** This option is not provided.
**Option C:** This option is not provided.
**Option D:** This option is not provided.

**Clinical Pearl / High-Yield Fact**
Normal CK and CK-MB levels after 2 days of chest pain do not rule out the possibility of an MI, especially if the patient has been taking beta-blockers or has a re-occurrence of MI.

**Correct Answer: D.**