Which of these BEST describes a scientific variable?
OA) a special type of experiment
OB) the outcome of an experiment
OC) a factor that may affect an experiment or investigation
OD) something that needs to remain the same for all experimental groups

C) a factor that may affect an experiment or investigation

Explanation:

This is the best answer. A and B can be eliminated. D describes a controlled variable which is more specific than a scientific variable, thus C is the best answer. It is the best description of  just a scientific variable.

explanation:

the universal gravitation equation. since the gravitational force is directly proportional to the mass of both interacting objects, more massive objects will attract each other with a greater gravitational force. if the mass of one of the objects is doubled, then the force of gravity between them is doubled.