Creatinine is not produced by

Options

A. Children
B. Pregnant women
C. Fasting persons
D. Healthy males

Answer

### Step-by-Step Solution:

1. **Understanding Creatinine Production**:
- Creatinine is a by-product of phosphocreatine, which is primarily found in skeletal muscles and the brain. It is produced when phosphocreatine is utilized to convert ADP (adenosine diphosphate) to ATP (adenosine triphosphate), the energy currency of the body.

2. **Identifying the Options**:
- The options given are:
- A) Children
- B) Pregnant women
- C) Fasting persons
- D) Healthy males

3. **Analyzing Each Option**:
- **Children**: They have active muscles and thus produce creatinine.
- **Pregnant Women**: They also produce creatinine due to metabolic activities.
- **Healthy Males**: They produce creatinine as they have active muscle metabolism.
- **Fasting Persons**: During fasting, muscle activity decreases significantly, leading to reduced utilization of phosphocreatine. Consequently, creatinine production is also reduced.

4. **Conclusion**:
- Since creatinine is not produced in significant amounts when a person is fasting due to decreased muscle activity, the correct answer is **C) Fasting persons**.