A student hypothesizes that a goldfish will be more active in a bowl that has red gravel than in a bowl with grey gravel. To test this hypothesis, the student places on goldfish in a bowl with red gravel and another in a bowl with grey gravel. The color of the gravel is the blank variable in the experiment.

A. Control
B. Responding
C. Dependent
D. Independent
Is the answer D?

correct

thanks ya .

Yes, the answer is D. The color of the gravel is the independent variable in the experiment. The independent variable is the variable that is intentionally changed or manipulated by the experimenter. In this case, the student is intentionally changing the color of the gravel by placing one goldfish in a bowl with red gravel and another goldfish in a bowl with grey gravel.

Just a quick explanation about the other variables in the experiment:

- Control variable: This is a variable that is kept constant or unchanged throughout the experiment in order to eliminate its potential effects on the outcome. In this case, there might be other factors that could influence the activity level of the goldfish, such as the amount of food, water temperature, or lighting conditions. To make sure the color of the gravel is the only factor being tested, the student would need to keep all these other variables consistent between the two bowls.

- Responding variable: This is the variable that is measured or observed to determine the effect of the independent variable. In this experiment, the student is measuring the activity level of the goldfish (how active they are) as the responding variable. By comparing the goldfish in the bowl with red gravel to the goldfish in the bowl with grey gravel, the student can see if the color of the gravel has any effect on their activity level.

- Dependent variable: This term is often used interchangeably with the responding variable. It represents the outcome or behavior that is being studied in response to the changes made to the independent variable. In this case, you can consider the activity level of the goldfish as the dependent variable.