Note the number line:
< ----|----|----|----|----|----|----|----|----|----|----|------------------------------------------------>
-7 -6 -5 -4 -3 -2 -1 0 1 2 3
There is 10 spaces inbetween -7 and 3
This means that D. 10 is your answer
Note that when counting distance between the two numbers, add them regardless of their sign, and you get your distance.
hope this helps
