Jennifer is testing her ability to lift different weights. which of the following could be a controlled variable

A. Amount of muscles
B. Time of day
C. Size of weights
D. None of the above

1 answer

In the context of an experiment where Jennifer is testing her ability to lift different weights, a controlled variable is a factor that is kept constant to ensure that the results of the experiment are valid.

Among the options provided:

A. Amount of muscles - This is not a controlled variable since it can vary greatly among individuals and even within Jennifer over time due to training.

B. Time of day - This could potentially be a controlled variable if the goal is to ensure that Jennifer's energy levels and body conditions are similar during different lift tests.

C. Size of weights - This is typically the independent variable that Jennifer is changing to test her lifting ability, so it is not a controlled variable.

D. None of the above - This option implies that none of the previous options could be considered a controlled variable.

Considering all options, B. Time of day could be a controlled variable if Jennifer decides to keep it constant throughout her testing sessions to avoid variations in performance due to time-related factors.

So, the best answer is B. Time of day.