Answer: D) rectangle
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Step-by-step explanation:
Since this is a parallelogram, the top and bottom sides are parallel. This in turn means the bottom left angle is 90 degrees. Recall that same side interior angles are supplementary when we have parallel lines. So if x was the bottom left angle, then 90+x = 180 solves to x = 90.
In short, the bottom left corner is a right angle.
Through similar steps, we can prove the other remaining interior angles are also 90 degrees each.
This figure is a rectangle because all four angles are 90 degrees.
We unfortunately don't have any info about the sides, so we don't know if the figure is a square or rhombus. If all four sides were the same length, then we have a rhombus. A figure being a rectangle and a rhombus means that it is also a square.