**Core Concept**
The oxygen-hemoglobin dissociation curve is a graphical representation of the relationship between the partial pressure of oxygen and the saturation of hemoglobin with oxygen. Factors that affect this curve include pH, temperature, and 2,3-bisphosphoglycerate (2,3-BPG) levels.

**Why the Correct Answer is Right**
Since the correct answer is not provided, let's discuss the general factors that affect the oxygen-hemoglobin dissociation curve. An increase in temperature, hydrogen ions (decrease in pH), or 2,3-BPG levels shifts the curve to the right, indicating a decreased affinity of hemoglobin for oxygen.

**Why Each Wrong Option is Incorrect**
**Option A:** Typically, factors like increased CO2, temperature, or 2,3-BPG would shift the curve to the right, affecting oxygen-hemoglobin dissociation.
**Option B:** Similar to Option A, certain factors can indeed impact the curve.
**Option C:** Again, this option might represent a factor that could potentially influence the curve, depending on what it is.

**Clinical Pearl / High-Yield Fact**
A key point to remember is that a right-shifted curve facilitates the release of oxygen to tissues, while a left-shifted curve indicates increased affinity of hemoglobin for oxygen, which can occur in conditions like alkalosis or decreased temperature.

**Correct Answer:** D.