a. dependent, independent
In a statistical analysis, the dependent variable is the variable that is being measured or observed, and the independent variable is the variable that is being manipulated or controlled. The dependent variable responds to the independent variable, and it is usually plotted on the Y-axis of a graph. The independent variable goes on the X-axis. For example, in a study on the effect of temperature on plant growth, the temperature would be the independent variable and plant growth would be the dependent variable. In this case, the dependent variable (plant growth) is responding to the independent variable (temperature), so plant growth would be plotted on the Y-axis and temperature would be plotted on the X-axis.