A stain was developed by a group of scientists to stain a particular cell organelle. The stain was tested on various tissues derived from an autopsy sample from a mammal. The organelles were counted. The results showed maximum number of the organelles in cells of brain, lesser in cells of heart, least in mature sperms and absent in erythrocytes. Identify the organelles from following options.

Options

A. Nissl bodies
B. Mitochondria
C. Golgi bodies
D. Endoplasmic reticulum

Explanation

To solve the question, we need to identify the cell organelle based on the provided information about its presence in various tissues. Let's break down the solution step by step.

### Step-by-Step Solution:

1. **Understanding the Problem**:
- We have a stain that was developed to identify a specific cell organelle.
- The organelle was tested on different tissues from a mammal, and the results showed varying quantities in different cell types.

2. **Analyzing the Results**:
- Maximum number of organelles in brain cells.
- Fewer organelles in heart cells.
- Least number in mature sperm.
- Absent in erythrocytes (red blood cells).

3. **Identifying the Organelles**:
- We have four options to consider:
- A) Nissl bodies
- B) Mitochondria
- C) Golgi Bodies
- D) Endoplasmic Reticulum

4. **Evaluating Each Option**:
- **Nissl Bodies**: These are primarily found in neurons (brain cells) and are associated with rough endoplasmic reticulum. They would be expected to be present in high numbers in brain cells but not in heart cells or mature sperm. They are also absent in erythrocytes.
- **Mitochondria**: These are present in all cells that require energy, including brain, heart, and sperm cells, but they are not absent in erythrocytes.
- **Golgi Bodies**: These are present in most cells but do not have a specific distribution pattern like the one described.
- **Endoplasmic Reticulum**: This organelle is involved in protein and lipid synthesis. The rough endoplasmic reticulum is abundant in cells with high protein synthesis, like neurons, and is less in heart cells, and very few in mature sperm. It is absent in erythrocytes.

5. **Conclusion**:
- Based on the analysis, the organelle that fits the description of being most abundant in brain cells, less in heart cells, least in mature sperm, and absent in erythrocytes is the **Endoplasmic Reticulum**.

### Final Answer:
The identified organelle is **D) Endoplasmic Reticulum**.