Which variables cause changes in the behavior of subjects being studied?

Changes in the behavior of subjects being studied can be influenced by various independent variables, including environmental factors, social interactions, and individual characteristics such as personality traits or past experiences. Additionally, experimental manipulations, such as rewards or punishments, can significantly affect behavior. Contextual factors, such as the presence of others or the setting of the study, also play a crucial role in shaping responses. Ultimately, the interplay between these variables determines the observed behavioral changes.