Fact 1: Most amphibians breathe with gills as larvae and with lungs as adults.

Fact 2: Frogs are the most durable of the amphibians.

Given the two facts above, answer the question "How do ost frogs breathe as tadpoles?" with the following options: 
- gills
 - sucking in air
 - oxygen
 - lungs
 - ligt
 - nektar
 - skin
 - ovaries


 

 gills        