To test best brand of paper towel what are the independent variables?

In testing the best brand of paper towels, the independent variables could include the brand of the paper towels being tested, the type of spills or messes (e.g., liquid, grease, dirt), and the conditions of the test (e.g., surface type, amount of liquid). Additionally, variables like the number of sheets used or the method of application (e.g., wiping or blotting) can also be adjusted to assess performance. By controlling these independent variables, the effectiveness of each brand can be compared systematically.