Which of the following statements describes one of the differences between tunicates and other chordates?

A) tunicates have 9 Hox genes whereas other chordates have 13 Hox genes
B) other chordates have 9 Hox genes whereas tunicates have 13 Hox genes
C) chordate characters in tunicates are more apparent in the adult stage than in the larval stage while all other chordates only exhibit these characteristics as larvae
D) lancelets and tunicates express different Hox genes that direct the development of the dorsal nerve cord