Q: Fact 1: Adult echinoderms have radial symmetry. Fact 2: All animals with radial symmetry live in water. Given the two facts above, where do all adult echinoderms live?

Choices:
[I] soil;
[II] desert;
[III] freshwater;
[IV] fossils;
[V] water;
[VI] Earth;
[VII] small;
[VIII] aquariums;
The answer is:
[V]