________is a living mechanical tissue.

Options

A.
B.
C.
D. both a and b

Answer

To answer the question "________ is a living mechanical tissue," we need to identify which type of tissue fits this description. Here’s a step-by-step solution:

### Step 1: Understand the Types of Mechanical Tissues
Mechanical tissues in plants provide structural support. The main types of mechanical tissues are:
- Parenchyma
- Collenchyma
- Sclerenchyma

### Step 2: Identify Living vs. Dead Tissues
- **Parenchyma**: This is a living tissue that primarily functions in storage and can also provide some support.
- **Collenchyma**: This is also a living tissue that provides mechanical support, particularly in young stems and petioles.
- **Sclerenchyma**: This tissue is made up of dead cells and provides rigid support.

### Step 3: Focus on the Living Mechanical Tissue
Since the question specifically asks for a living mechanical tissue, we can eliminate sclerenchyma because it consists of dead cells.

### Step 4: Confirm the Correct Answer
Among the living tissues, collenchyma is specifically known for providing mechanical support while being alive. Therefore, the correct answer to the question is collenchyma.

### Final Answer
**Collenchyma** is a living mechanical tissue.

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