Mollusks have a circulatory system with one or two hearts that pump blood.
An abalone is a shellfish or mollusk.
Abalone have a circulatory system with one or two hearts that pump blood.
What has a circulatory system with one or two hearts that pump blood?

[1] a fish
[2] sharks
[3] abalone
[4] elephants
[5] humans
[6] crocodiles
[7] giraffes
[8] fur seals