The oxygen - haemoglobin dissociation curve will show a right shift in case of

Options

A. high `PCO_(2)`
B. high `PO_(2)`
C. low `PCO_(2)`
D. less `H^(+)` concentrations

Explanation

### Step-by-Step Solution:

1. **Understand the Oxygen-Hemoglobin Dissociation Curve**:
- The oxygen-hemoglobin dissociation curve illustrates the relationship between the partial pressure of oxygen (pO2) and the saturation of hemoglobin with oxygen. It typically has a sigmoid shape.

2. **Identify Shifts in the Curve**:
- A right shift in the curve indicates that hemoglobin has a decreased affinity for oxygen, meaning it releases oxygen more readily to the tissues.
- Conversely, a left shift indicates an increased affinity for oxygen.

3. **Factors Causing Right Shift**:
- The right shift can be caused by several physiological factors:
- Increased partial pressure of carbon dioxide (pCO2)
- Increased temperature
- Increased hydrogen ion concentration (lower pH)
- Increased levels of 2,3-DPG (2,3-diphosphoglycerate)

4. **Analyze the Given Options**:
- The options provided are:
- High partial pressure of carbon dioxide
- High partial pressure of oxygen
- Low partial pressure of carbon dioxide
- Less hydrogen concentration
- Among these, the option that corresponds to a right shift is **high partial pressure of carbon dioxide**.

5. **Conclusion**:
- Therefore, the oxygen-hemoglobin dissociation curve will show a right shift in the case of a **high partial pressure of carbon dioxide**.