Animal tissues differ from plant tissues because animal tissues:

The correct option is Are mostly living and flexible.

To understand why animal tissues differ from plant tissues, let us compare their structural and functional requirements:

1. Living vs. Non-living Cells:
Animals move around in search of food, mates, and shelter, consuming more energy in the process. Consequently, most tissues in animals are composed of living cells that actively carry out metabolic functions to support movement and complex activities. In contrast, plants are stationary (sedentary) and require continuous structural support to stand upright, so a large portion of plant tissues (such as sclerenchyma and xylem vessels) consists of dead, supportive cells.

2. Flexibility vs. Rigidity:
Animal cells lack rigid cell walls, having only a flexible plasma membrane. This makes animal tissues far more flexible and pliable, allowing for muscle contraction, limb movement, and dynamic tissue shapes. Plant cells, on the other hand, possess rigid cell walls made of cellulose, giving them a stiff and fixed structure.

3. Growth Pattern:
Animals exhibit uniform, limited growth throughout their body up to a certain maturity level, whereas plants show localized, unlimited growth due to specialized regions called meristems.

Therefore, the key characteristic distinguishing animal tissues from plant tissues is that animal tissues are mostly living and flexible.