A waitress is interested in whether providing candy at the end of a meal to her customers can have a positive impact on the tips she receives. She either does or does not provide candy to her customers when she delivers the final check

The waitress then records the amount of the tip she receives from the dining party. What would the act of providing or not providing candy be in this study?
a. a construct
b. an independent variable
c. a random variable
d. a dependent variable

b