A person is undergoing prolonged fasting. His urine will be found to contain abnormal quantities of –

Options

A. Fats
B. Amino acids
C. Ketone body
D. Glucose

Answer

### Step-by-Step Solution:

1. **Understanding Prolonged Fasting**: When a person undergoes prolonged fasting, the body starts to utilize its energy reserves. Initially, the body uses glucose from glycogen stores, but these stores are limited.

2. **Energy Source Shift**: As fasting continues, the body shifts its primary energy source from glucose to fats. This is because glycogen stores become depleted, and the body needs to find an alternative source of energy.

3. **Oxidation of Fat**: The fats stored in the body are broken down through a process called lipolysis. This process leads to the oxidation of fatty acids, which is a key metabolic pathway during fasting.

4. **Production of Ketone Bodies**: During the oxidation of fatty acids, the liver converts these fatty acids into ketone bodies. Ketone bodies are water-soluble molecules that serve as an alternative energy source for various tissues, including the brain.

5. **Excretion of Ketone Bodies**: As the concentration of ketone bodies increases in the blood due to their production from fat oxidation, they are eventually excreted in the urine. This leads to the presence of abnormal quantities of ketone bodies in the urine.

6. **Conclusion**: Therefore, in a person undergoing prolonged fasting, the urine will be found to contain abnormal quantities of ketone bodies.

### Final Answer:
The urine will contain abnormal quantities of **ketone bodies**.

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