**Core Concept**
The management of myocardial infarction (MI) involves the use of various pharmacological agents to restore blood flow, reduce ischemic damage, and prevent complications. The correct use of these agents is crucial in improving patient outcomes.

**Why the Correct Answer is Right**
In MI, certain agents are contraindicated or not used due to their potential to worsen cardiac function or increase mortality. The correct answer is an agent that is not typically used in the management of MI. For example, **non-selective beta-blockers** can worsen heart failure and are generally avoided in acute MI. In contrast, **selective beta-1 blockers**, such as metoprolol, are commonly used to reduce heart rate and blood pressure.

**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as non-selective beta-blockers can worsen heart failure and are generally avoided in acute MI.
* **Option B:** This option is incorrect as **calcium channel blockers** can be used in certain cases of MI, such as Prinzmetal's angina or hypertension, but are not universally contraindicated.
* **Option C:** This option is incorrect as **nitrates** are commonly used in MI to reduce myocardial oxygen demand and alleviate chest pain.

**Clinical Pearl / High-Yield Fact**
In the management of MI, it's essential to use medications that have been shown to improve outcomes, such as beta-blockers, ACE inhibitors, and statins.

**Correct Answer: A. Non-selective beta-blockers.**