Answer:
a) 5
Explanation:
Graphically, b - a can be represented by placing a vector of the same magnitude of a but opposite orientation at the end of vector b. Let's call this vector -a. |b-a| will be the vector that share origin with b and end with -a. The minimum value that the magnitude of |b-a| can have will occur when -a have the same direction of b but opposite orientation, and the maximum value when -a have the same direction and orientation. Mathematically, this would be:
|b-a|min = 12 - 5 = 7
|b-a|max = 12 - (-5) = 17
Notice that 5 is the only option that is not in this range, so the answer is a.