Answer: In this situation, it is not correct to say that either d or g could be the independent variable.
Step-by-step explanation: In this scenario g is the independent variable and d is the dependent variable.
The independent variable is the variable that is being intentionally manipulated or changed in an experiment or analysis, while the dependent variable is the variable that is being measured or observed. In this case, it is clear that the quantity of glasses (g) is the independent variable because it is being intentionally varied in order to observer the corresponding changes in the cost (d).
While it is true that d and g are related (e.g., increasing g will result in an increase in d), this does not imply that d could be the independent variable. This is because changes in d are a consequence of changes in g, not the other way around.