Well I know this is not linear becuase then the y-values would be going up by a constant number. So, B and C are gone. Personally, A looks a bid odd. So, If I were you I'd go with D.
Just my opinion, not 100%
Since you don't provide the coordinates of the point W, I will help you in a general form anyway. In the Figure below is represented the segment that matches this problem. We have two endpoints U and V. So, by using the midpoint formula we may solve this problem:

Therefore:

So we know
but we also must know 
Finally, knowing the points U and W we can find the endpoint V.
One positive and one negative
Answer:
3
Step-by-step explanation: