In animals, the hox genes encode a family of transcription factors that are important for proper development of embryonic segments and are widely conserved in organisms. The figure below shows the embryonic segments in which one such gene, Hoxc6, is expressed in the embryo of a mouse, a chick, and a goose. Embryonic segments are counted from the anterior end.

During the formation of vertebrae, the most anterior embryonic segment that expresses Hoxc6 marks the end of the cervical (neck) vertebrae and the beginning of the thoracic (rib) vertebrae. All mammals have seven cervical vertebrae.

Which of the following statements is most likely to be true?

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Mammals include mice. Counting from the anterior end, the 8^th segement corresponds to the first one where Hoxc6 is expressed.

There is no information regarding thoracic vertebrae.

Hoxc6 is not expressed in the same segments of the chick and the mouse.

Since the chick and goose express Hoxc6 at different positions, it is untrue that all bird embryos express it in the same vertebra.