The answer is C.
We know that, the area of a parallelogram is the product of its any side and the corresponding altitude (or height).
Here, when AB is base, the height is DL.
∴ Area of parallelogram = AB × DL.
And when AD is base, the height is BM.
∴ Area of parallelogram = AD × BM
And when BC is base, the height is BM.
∴ Area of parallelogram = BC × BM
And when DC is base, the height is DL.
∴ Area of parallelogram = DC × DL
So, the area of the parallelogram is DC × DL