What would cause the gravitational force to be different in different locations? a. a difference elevation b. a difference population c. a difference in mass

It would be A. For example the further you go down ocean the more pressure there is. A more in depth explanation is that the Earth core is where gravity originates, and that's what keeps the moon orbiting us and not flying into space. The closer you are to the core the more pressure you have to endure.  

Option A. Difference in elevation

Explanation:

Gravitational force is different in the different locations. It's true.

Gravitational force is inversely proportional to the square of the distance from the center of the earth.

g ∝

When we are at equator, gravitational force is less as compared to the poles. (Since poles are nearer to the center of the earth than equator)

Option A. is the answer.

i think that is new experiments yield untrustworthy data and should be carefully considered, because you don't know what will happen with the experiments.