The Free-Swimming Tunicate Larva Resembles a Tadpole

The free-swimming tunicate larva resembles a tadpole.Once it settles headfirst onto a solid surface,the tail and notochord disappear and the nerve cord shrinks to nearly nothing.The adults,which are usually sessile,retain only the pharyngeal slits.Neither adult nor larva is segmented.Tunicates do retain what trait as adults which makes them resemble other chordates?

A) radial symmetry
B) asymmetry
C) cephalization
D) endothermy
E) incomplete digestive tract