To solve this problem, we need to determine which factor does not affect stomatal movement. Let's analyze each option:$\newline \bullet$O$_2$ concentration:$\newline$ - Stomatal movement is primarily regulated by factors such as light, CO$_2$ concentration, and temperature.$\newline$ - Oxygen concentration does not have a significant effect on stomatal opening or closing.$\newline$ - Therefore, stomatal movement is not affected by O$_2$ concentration.$\newline \bullet$Light:$\newline$ - Light is a major factor influencing stomatal movement.$\newline$ - Stomata generally open in the presence of light to facilitate photosynthesis.$\newline \bullet$Temperature:$\newline$ - Temperature can affect the rate of transpiration and stomatal movement.$\newline$ - High temperatures can cause stomata to close to prevent water loss.$\newline \bullet$CO$_2$ concentration:$\newline$ - CO$_2$ concentration is a key factor in stomatal regulation.$\newline$ - High levels of CO$_2$ can cause stomata to close, while low levels can cause them to open.$\newline$Based on this analysis, the correct option is Option 1: O$_2$ concentration, as it does not affect stomatal movement.