Fact 1: Vertebrate chordates have a backbone. Fact 2: Chordates Chordates Chordates include fish, amphibians, reptiles, birds, and mammals. Given the two facts above, fish, amphibians, reptiles, birds, and mammals have what?
Choose from:
[I] food;
[II] fur and fat;
[III] backbone;
[IV] power;
[V] four limbs;
[VI] retina;
[VII] vision;
[VIII] competition;
Answer:
[III]