characteristics of chordates?

Question

Which of the following is not a characteristic of chordates?

a. All chordates have a spinal chord protected by a vertebral column.
b. All vertebrates have a notochord.
c. All chordates have tails sometime in their development.
d. All chordates have pharyngeal slits.
e. All chordates have nerve chords.

Answer 1

a