Which one of the following plant tissues has dead cells?

Plant tissues are categorized based on their structure and function. Parenchyma cells are the most common living cells, responsible for metabolic functions like photosynthesis and storage. Collenchyma cells are also living at maturity, characterized by unevenly thickened primary cell walls that provide flexible support to growing organs [1][3]. The epidermis is the primary dermal tissue, consisting of a single layer of living cells that protect the plant [1]. In contrast, sclerenchyma tissue is composed of cells that are typically dead at maturity [2]. These cells possess thick, secondary cell walls heavily reinforced with lignin, a complex polymer that provides rigid structural support and hardness [3]. Sclerenchyma exists in two forms: elongated fibers and irregular sclereids, both of which function as structural scaffolding only after the living protoplasm is lost.

Sources

1. [1] https://oertx.highered.texas.gov/courseware/lesson/1766/student/?section=2
2. [3] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/plant-tissue
3. [2] https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/sclereids