Read the given passage.
There are 3 types of blood cells, X, Y and Z. X is biconcave disc shaped and contains haemoglobin. Y protects us from many diseases and helps fight infection. Z helps in blood clotting.
Select the incorrect option regarding X, Y and Z.

Options

A. People living in higher altitudes have higher X count as compared to people living in plains.
B. High Y count indicates some infection in the body.
C. Decrease in Z count also indicates infections like dengue.
D. People with very low X count continue to bleed even from minor injury as their blood does not clot.

Explanation

To solve the question regarding the types of blood cells X, Y, and Z, we need to analyze the information provided in the passage and the video transcript. Here’s a step-by-step breakdown:

### Step 1: Identify the Types of Blood Cells
- **Cell X**: Described as biconcave disc-shaped and contains hemoglobin. This is characteristic of **Red Blood Cells (RBCs)**.
- **Cell Y**: Protects against diseases and helps fight infections. This is characteristic of **White Blood Cells (WBCs)**.
- **Cell Z**: Helps in blood clotting. This is characteristic of **Platelets (Thrombocytes)**.

### Step 2: Analyze the Functions of Each Blood Cell
- **X (RBCs)**: Responsible for transporting oxygen throughout the body due to the presence of hemoglobin.
- **Y (WBCs)**: Involved in the immune response and fighting infections.
- **Z (Platelets)**: Essential for blood clotting to prevent excessive bleeding.

### Step 3: Identify the Incorrect Statement
Now, we need to find the incorrect option regarding these blood cells. Based on the information:
- The statement that **X is responsible for blood clotting** is incorrect because X refers to Red Blood Cells, which do not play a role in clotting; that role belongs to Platelets (Z).

### Conclusion
The incorrect option regarding X, Y, and Z is that X (RBCs) is responsible for blood clotting.

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