To answer this question we need to remember some properties for any parallelogram:
• Two pairs of opposite sides are equal in length.
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• Two pairs of opposite angles are equal in measure.
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• The diagonals bisect each other.
We notice that in the figure QSRP opposite sides are equal in length then we conclude that this is a parallelogram.
In figure RSUT we notice that the diagonals bisect each otherm then we conclude that this is a parallelogram.
In figure KLNM we notice that none of the properties stated before are fullfill, then this is not necesarrily a parallelogram.
In figure BDCA we notice that alternate interior angles are equal, this means that segments BD and CA are parallel, we also notice that the other segments are parallel; therefore this is a parallelogram.