Fluid with variable amount of materials is

Options

A. Urine
B. Cerebrospinal fluid
C. Blood
D. Lymph.

Answer

**Step-by-step Solution:**

1. **Understanding the Question**: The question asks for a fluid that contains a variable amount of materials. This implies that the fluid composition can change based on different factors.

2. **Analyzing the Options**:
- **Urine**: Urine is primarily composed of water (91-96%) and contains various inorganic salts and organic compounds. However, its composition is relatively consistent.
- **Cerebrospinal Fluid (CSF)**: CSF is a clear, colorless fluid with low protein concentration and is mostly acellular. Its composition is also relatively stable and does not vary significantly.
- **Blood**: Blood consists of plasma and cellular components (red blood cells, white blood cells, platelets). While plasma can vary in terms of the solutes it carries, blood as a whole does not fit the description of a fluid with a highly variable composition.
- **Lymph**: Lymph is a clear to white fluid that contains a variable amount of materials, primarily white blood cells, especially lymphocytes. Its composition can change based on the immune response and the presence of pathogens.

3. **Identifying the Correct Answer**: After analyzing all options, lymph is the only fluid that is characterized by a variable composition due to the presence of different types of white blood cells and other materials.

4. **Conclusion**: The correct answer to the question is **lymph**.

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