Fact 1: Adult echinoderms have radial symmetry.

Fact 2: Starfish and sea urchins are also echinoderms.

Given the two facts above, answer the question "what adults have radial symmetry?" with the following options: 
- sea urchins
 - graptolites
 - humans
 - fur seals
 - barnacles
 - insects
 - h2o
 - gastropod shells


 

 sea urchins        