The evolution of the eohippus into the modern day horse is an example of metamorphosis.
A character change would be internal, stasis means to remain the same and extinction is the end of an organism, the eohippus is extinct, but the question is asking specifically about it's change. Therefore choice 4 is the correct answer.
I love this story! His greatest fear is turning out to be just like his father who is lazy, cowardly, and unable to support his family
