Enucleated living plant cells are

Options

A. RBC
B. Tracheids
C. Mature sieve elements
D. Companion cells

Answer

To solve the question "Enucleated living plant cells are," we need to analyze the options provided and determine which one fits the criteria of being both enucleated (lacking a nucleus) and living. Here's a step-by-step breakdown:

### Step 1: Understand the Terms
- **Enucleated**: This means that the cell does not have a nucleus.
- **Living Cells**: These are cells that are metabolically active and functioning.

### Step 2: Analyze Each Option
1. **RBCs (Red Blood Cells)**:
- RBCs are enucleated cells, but they are found in animals, not plants. Therefore, this option is incorrect.

2. **Trachea**:
- Trachea refers to tracheids, which are part of the xylem in plants. These cells are dead at maturity and do not function as living cells. Thus, this option is also incorrect.

3. **Mature Sieve Elements**:
- Mature sieve elements are specialized cells in the phloem tissue of plants. They are indeed enucleated at maturity but are still considered living cells as they participate in the transport of nutrients. This option is correct.

4. **Companion Cells**:
- Companion cells are also part of the phloem and are nucleated. They assist sieve elements but do not fit the criteria of being enucleated. Therefore, this option is incorrect.

### Step 3: Conclusion
Based on the analysis, the correct answer to the question "Enucleated living plant cells are" is **Mature Sieve Elements**.

### Final Answer:
**Mature Sieve Elements (Option C)**

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