Answer:
Yes, this hypothesis is true. The ancestor of whale belongs to amphibians.
Step-by-step explanation:
Amphibians are those organisms which has the ability to live both on land and water. Wales are evolved from land animals such as ungulates. Ungulates are those organisms which belongs to mammals and having hooves. For example, deer, cow, horse and zebra etc. The ancestor of whale lives on land 50 million years ago. So the hypothesis is true.