This shape is a trapezoid because it has only one pair of parallel lines.
The line created by (0,2) and (-3,0) is parallel to the line created by (4,2) and (4,0).
In addition:
It CAN NOT be a parallelogram because it does not have two pairs of opposite parallel lines.
It CAN NOT be a rectangle because it does not have two pairs of opposite parallel lines of equal measure.
It CAN NOT be a rhombus because it is not a parallelogram.