The elongated, thick-walled and tapering cells are

Options

A. Parenchymatous
B. Collenchymatous
C. Chlorenchymatous
D. Sclerenchymatous

Answer

To answer the question regarding the elongated, thick-walled, and tapering cells, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Types of Cells**: We need to analyze the given options: parenchymatous, collenchymatous, chlorenchymatous, and sclerenchymatous cells.

2. **Examine Parenchyma**:
- Parenchyma cells are known for being thin-walled and made primarily of cellulose.
- They are not elongated or thick-walled, so they can be eliminated.

3. **Examine Collenchyma**:
- Collenchyma cells are also characterized by being thin-walled, composed of cellulose and pectin.
- They provide support but do not have thick walls, so they can also be eliminated.

4. **Examine Chlorenchyma**:
- Chlorenchyma is a type of parenchyma that contains chloroplasts and is involved in photosynthesis.
- Like parenchyma, these cells are thin-walled and made of cellulose, thus can be eliminated.

5. **Examine Sclerenchyma**:
- Sclerenchyma cells are known for their thick walls, which are primarily made of lignin.
- These cells are typically elongated and tapering, making them suitable for structural support.

6. **Conclusion**: Based on the analysis, the correct answer is that the elongated, thick-walled, and tapering cells are **sclerenchymatous cells**.

### Final Answer:
The elongated, thick-walled, and tapering cells are **sclerenchyma**.