Concept:Irritability is the ability of a cell to detect and react to changes in its environment.
Explanation:Cells are constantly exposed to internal and external signals, such as light, heat, pressure, or chemical changes.
Irritability means the cell can respond appropriately to these signals.
This response may include movement, secretion, or a change in activity.
Options B, C, and D are general cellular functions, not directly linked to irritability.
Therefore, the characteristic of cells related to irritability is specifically the ability to respond to stimuli.
Answer:A. Ability to respond to stimuli