Hemichordates have now been placed with the nonchordates, close to echinoderms, because true
A. notochord is absent.
B. pharyngeal gill-slits are lacking.
C. dorsal nerve cord is absent.
D. heart is lacking.
Correct Answer :
A. notochord is absent.
Hemichordates have now been placed with the non-chordates because true notochord is absent in them but a buccal diverticulum is present in pre-oral region which is often regarded as stomochord.