Which transformation can be used to prove that this parallelogram is symmetrical?

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CLEAR CHECK

Applying Transformation 1 twice carries the parallelogram onto itself.

Applying Transformation 2 carries the parallelogram onto itself.

Applying Transformation 1 carries the parallelogram onto itself.

Applying both transformations must be applied to carry the figure onto itself.

Applying Transformation 1 carries the parallelogram onto itself.