Q: Cephalochordates have a notochord and nerve cord but not a?


Read this paragraph and choose the correct option from the provided answers:

Cephalochordata: Cephalochordates include the lancelets ( Figure below ), fish-like marine animals often found half-buried in the sand. Cephalochordates have a notochord and nerve cord but no backbone.

 Choices:

- digestive system

- nervous system

- brain

- backbone


A:
backbone