Opposite sides ofa parallelogram are equal.
Therefore, AB= CD and AD= BC.
Diagonals of a parallelogram bisect each other.
Measure of opposite angles of a parallelgram also equal.
So, <ADC= <ABC and <BAD=<BDC
Since diagonal of a parallelogram bisect each other so AC and BD are intersecting at the point E.
Hence, AE= CE and BE= DE.
Hence, the correct choice is 4)AE=CE.
