Fact 1: Amphibians have a relatively complex circulatory system with a three-chambered heart.

Fact 2: Frogs, toads and salamanders are amphibians.

Given the two facts above, answer the question "What sort of circulatory system do frogs, toads, and salamanders share?" with the following options: 
- live birth
 - It helps them survive
 - matter vibrating
 - two-chambered heart
 - Veins and arteries.
 - biological diversity
 - three-chambered heart
 - four-chambered heart


 

       three-chambered heart  