The option depicting the correct partial pressure (in mm Hg) is :

Options

A. `{:(pO_2" in alveolar air ",pCO_2" deoxygenated blood",pO_2" in oxygenated blood",pCO_2" in tissues"),(104,40,94,45):}`
B. `{:(pO_2" in alveolar air ",pCO_2" deoxygenated blood",pO_2" in oxygenated blood",pCO_2" in tissues"),(94,45,104,40):}`
C. `{:(pO_2" in alveolar air ",pCO_2" deoxygenated blood",pO_2" in oxygenated blood",pCO_2" in tissues"),(104,40,45,94):}`
D. `{:(pO_2" in alveolar air ",pCO_2" deoxygenated blood",pO_2" in oxygenated blood",pCO_2" in tissues"),(104,45,94,45):}`

Answer

To solve the question regarding the correct partial pressures of gases, we will analyze the partial pressures of oxygen (O2) and carbon dioxide (CO2) in different contexts, such as in alveolar air, deoxygenated blood, and oxygenated blood.

### Step-by-Step Solution:

1. **Understanding Partial Pressure**:
- Partial pressure refers to the pressure exerted by an individual gas in a mixture of gases. It is crucial in understanding gas exchange in the respiratory system.

2. **Partial Pressure of O2 in Alveolar Air**:
- The typical partial pressure of O2 in alveolar air is approximately 104 mm Hg. This is higher than the partial pressure of O2 in the atmosphere (159 mm Hg) due to the mixing of gases in the lungs.

3. **Partial Pressure of CO2 in Deoxygenated Blood**:
- In deoxygenated blood, which is blood that has released its oxygen to tissues and picked up carbon dioxide, the partial pressure of CO2 is typically around 45 mm Hg. This is higher than the partial pressure of O2 in the same blood, which is about 40 mm Hg.

4. **Partial Pressure of O2 in Oxygenated Blood**:
- In oxygenated blood, the partial pressure of O2 is generally between 94 to 95 mm Hg. This indicates that the blood is rich in oxygen after passing through the lungs.

5. **Comparing Options**:
- Now we will compare the given options with the established values:
- **Option 1**: O2 in alveolar air = 104 mm Hg (correct), CO2 in deoxygenated blood = 40 mm Hg (incorrect, should be 45 mm Hg).
- **Option 2**: O2 in alveolar air = 94 mm Hg (incorrect, should be 104 mm Hg).
- **Option 3**: O2 in alveolar air = 104 mm Hg (correct), CO2 in deoxygenated blood = 45 mm Hg (correct).
- **Option 4**: O2 in alveolar air = 104 mm Hg (correct), CO2 in deoxygenated blood = 45 mm Hg (correct), O2 in oxygenated blood = 94-95 mm Hg (correct), CO2 in tissues = higher than O2 (correct).

6. **Conclusion**:
- The correct option that depicts the accurate partial pressures is **Option 4**. This option correctly states the partial pressures for O2 and CO2 in the relevant contexts.