**Core Concept**
Hypoxic injury, also known as anoxia or ischemia, occurs when cells are deprived of oxygen. This can lead to cellular damage and death. The sensitivity of cells to hypoxic injury varies depending on their metabolic rate and energy requirements.

**Why the Correct Answer is Right**
Purkinje fibers in the heart are the most sensitive cells to hypoxic injury. This is because they have a high metabolic rate and rely heavily on aerobic metabolism to generate energy. When oxygen is scarce, Purkinje fibers are quickly depleted of ATP and become unable to function, leading to cardiac arrhythmias and potentially fatal outcomes. The high energy demands of Purkinje fibers make them particularly vulnerable to hypoxia.

**Why Each Wrong Option is Incorrect**
* **Option A:** Neurons are sensitive to hypoxia, but they are not the most sensitive cells. While neurons rely on aerobic metabolism, they have a lower metabolic rate than Purkinje fibers and can survive for longer periods without oxygen.
* **Option B:** Red blood cells are not sensitive to hypoxia because they do not rely on aerobic metabolism to generate energy. Instead, they use anaerobic glycolysis to produce ATP.
* **Option C:** Myocytes (skeletal muscle cells) are sensitive to hypoxia, but they are not as sensitive as Purkinje fibers. Myocytes can survive for longer periods without oxygen due to their lower metabolic rate and ability to use anaerobic glycolysis.

**Clinical Pearl / High-Yield Fact**
In clinical settings, hypoxic injury can be prevented or minimized by maintaining adequate oxygenation of tissues, particularly in high-risk areas such as the heart and brain. This can be achieved through various means, including mechanical ventilation, supplemental oxygen therapy, and perfusion of critical organs.

**Correct Answer:** C.