Assertion : Lymph in lymphatic system is known as tissue fluid
Reason : It consists of plasma proteins, RBCs and WBCs.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reason is false
D. If both assertion and reason are false

Explanation

To analyze the given assertion and reason, we will break down the statements and evaluate their validity step by step.

### Step 1: Understanding the Assertion
The assertion states: "Lymph in the lymphatic system is known as tissue fluid."

- **Explanation**: Lymph is indeed a fluid that circulates in the lymphatic system. It is derived from interstitial fluid, which bathes the cells in tissues. As lymphatic vessels collect this fluid, it is often referred to as tissue fluid because it helps in transporting nutrients, waste products, and immune cells to and from tissues.

### Step 2: Evaluating the Reason
The reason states: "It consists of plasma proteins, RBCs, and WBCs."

- **Explanation**: This statement is incorrect. Lymph does contain some plasma proteins and white blood cells (WBCs), but it does not contain red blood cells (RBCs) under normal circumstances. RBCs are primarily found in the blood, not in lymph. Therefore, the presence of RBCs in lymph is a misconception.

### Step 3: Conclusion
- The assertion is **true**: Lymph is known as tissue fluid.
- The reason is **false**: Lymph does not consist of RBCs; it contains plasma proteins and WBCs but not RBCs.

### Final Answer
Thus, the correct option is that the assertion is correct, but the reason is incorrect. Therefore, the answer is **Option C**.

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