The yellow colour of urine is due to the presence of

Options

A. urea
B. bilirubin
C. uric acid
D. Urochrome

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the substance responsible for the yellow color of urine.

2. **Identifying the Options**: Review the options provided (though not listed here, we know they include substances like urea, bilirubin, uric acid, and urochrome).

3. **Analyzing Urochrome**: Urochrome is identified as a pigment that gives urine its yellow color. It is a breakdown product of hemoglobin.

4. **Source of Urochrome**: Urochrome is formed from the breakdown of hemoglobin, which is found in red blood cells (RBCs). When RBCs are destroyed or worn out, hemoglobin is released and subsequently broken down, leading to the formation of urochrome.

5. **Excretion Process**: Urochrome is excreted by the kidneys along with urine, contributing to its yellow color.

6. **Conclusion**: Based on the analysis, the correct answer to the question is that the yellow color of urine is due to the presence of urochrome.

### Final Answer:
The yellow color of urine is due to the presence of **urochrome**.

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