How do you find the independent dependent and controlled variable when testing 4 brands of root beer in a blind consumer taste test?

- Brand of root beer (4 different brands)

Dependent Variable:

- Consumer preference (which brand is preferred the most)

Controlled Variables:

- Type of root beer (all must be the same type, such as regular or diet)

- Temperature of the root beer (all samples must be served at the same temperature)

- Amount of root beer served to each consumer (all samples must be the same size)

- Environment in which the taste test is conducted (all consumers must be in the same room, with no distractions)