**Core Concept**
Inotropic agents are pharmacological agents that increase the contractility of the heart muscle (cardiac myocytes), thereby improving cardiac output. This is crucial in treating conditions where cardiac function is compromised, such as heart failure.

**Why the Correct Answer is Right**
Inotropic agents work by either increasing the availability of calcium ions (Ca2+) to the cardiac myocytes, enhancing the sensitivity of the contractile apparatus to calcium, or by increasing the release of calcium from the sarcoplasmic reticulum. Examples of inotropic agents include dobutamine, dopamine, norepinephrine, and milrinone. These agents are commonly used in critical care settings to support patients with compromised cardiac function.

**Why Each Wrong Option is Incorrect**
**Option A:**
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