Answer: The correct answer is- A cat.
Notochord is the main longitudinal structural element of chordates that is present in the early embryonic development of the vertebrates. In later development of vertebrates ( in adults), this structure becomes part of the vertebral column.
It is a midline structure in vertebrate embryos that plays an essential role in the patterning of the surrounding tissues.
Out of the given options, only cat belongs to chordata.
Thus, cat exhibits notochord in the embryonic stage.