In a controlled scientific experiment, A. all variables are kept constant. B. one or more variables are kept constant. C. no variables are kept constant. D. only one variable can be kept constant. Reset

A, all variables are kept constant. In order to get accurate results when doing an experiment, everything should be kept as similar as possible to ensure accurate results.

Mass is the amount of matter in an object.  weight is the measurement of the pull of gravity on an object.  say for example, you travel to the moon which has a different gravitational field compared to the gravitational field of earth. (gravitational fields: earth = 1, moon = 0.165)  now when you are on the moon, the pull of gravity on you is different than on the earth. and as weight is the measurement of the pull of gravity on an object, that means yes, your weight can and will change on the moon.  however, on the moon, on earth or even on jupiter, the amount of mass inside of you remains the same. meaning your physical mass remains constant.  in conclusion it is possible for your weight to change as your mass remains constant. 

The answer you are looking for is option d