We could simply plot the other sets of points and find out which set forms a rectangle with the two given points, (-3,2), and (1,2).
However, that seems either too difficult or too easy, such that no one offered a solution that way. I will still leave that option open for anyone who wishes to try it.
The problem is very much suited for a solution by look at the numbers, in other words, by inspection.
The given (fixed) points are (-3,2) and (1,2), they both lie on the horizontal line y=2. From the properties of a rectangle, the other two points must be parallel, hence they should also lie on a horizontal line.
Looking at the 4 possible options, we notice that all options have the points lie on the horizontal line y=5, evidenced by the fact that all points have a y-coordinate of y=5.
Thus our only job is to find points such that they line up vertically with the two given points (-3,2), (1,2). In other words, the other two points must have the coordinates (-3, 5), (1,5) which match the x-coordinates of the given points.
So the above is the method by inspection which can be applied given the two given points lie on a horizontal (or vertical) line.
