In plants _________ is a dead mechanical tissue.

Explanation

**Step-by-Step Solution:**

1. **Identify the Type of Tissue:** In plants, there are various types of tissues, including meristematic, permanent, and mechanical tissues. We need to focus on mechanical tissues.

2. **Understand Mechanical Tissues:** Mechanical tissues in plants provide support and protection. They can be classified into two categories: living and dead tissues.

3. **Focus on Dead Mechanical Tissues:** Among the mechanical tissues, some are dead at maturity. The primary dead mechanical tissue in plants is known as sclerenchyma.

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