Fact 1: Mollusks have a circulatory system with one or two hearts that pump blood.

Fact 2: Mussels are bivalve mollusks.

Given the two facts above, answer the question "what have a circulatory system?" with the following options: 
- protist
 - fur seals
 - veins
 - mammals
 - animals
 - bacteria
 - mussels
 - sharks


 

       mussels  