What type of body cell is characterized by its inability to regenerate and is replaced with scar tissue?

Permanent or fixed cells are characterized by their inability to regenerate and are replaced with scar tissue following injury. This category includes specialized cells such as neurons and cardiac muscle cells, which have a limited capacity to divide and heal. When these types of cells are damaged, the body does not replace them with new, functional cells; instead, fibroblasts produce collagen and other extracellular matrix components to form scar tissue.

In contrast, labile cells are capable of continuous division and can regenerate after injury, such as epithelial cells in the skin or gastrointestinal tract. Stable cells can regenerate but typically only do so in response to injury or increased demand, like hepatocytes in the liver. Regenerative cells refer more broadly to cells that have the capacity to undergo regeneration, which is contrary to the characteristics of permanent cells. Therefore, the defining feature of permanent or fixed cells is their inability to replicate and their replacement with scar tissue, making this the correct choice.