Answer:
C
Step-by-step explanation:
The answer is 1/9 or C.
About the easiest way to figure this out is to take the force of gravity to be 1 Newton when G*m1*m2 = 1 and r = 1 meter.
Now if you change the distance to 3 meters then
G*m1*m2 still = 1
but R becomes 3
F = 1 / 3^2
F = 1/9