Answer:
The correct option is A. they evolved from land mammals.
Explanation:
The process of evolution explains how closely one organism is to another based on their common ancestors. Scientists believe that those organisms which show many similarities in their structures or functions might have evolved from a common ancestor in the past.
As in the above-mentioned question, scientists have observed that cetaceans lack gills and breath air, this is a property of land mammals. The cetaceans have fin bones which are similar to the limb bones. As limb bones are present in land mammals, hence they cetaceans and land mammals might have common ancestors in the past.
Answer
Option A
Explanation:
It has been demonstrated that Cetaceans have evolved from a common ancestor that was able to walk (mammals) even though modern Cetaceans do not have ankles or ankle bones, fossil whales do. The anatomy of fossil feet and ankles showed that ancestral whales had hooves.
