Answer:
Selection might be the reason why a given organism does not change over generations
Explanation:
This statement might be a very rare case in nature to be observed. There are some particular scenarios that can provide such cases. Imagine you are on an island that the environment conditions are not too much variable. In such conditions, the organisms that live on that island does not suffer a high amount of selective pressure from the environment. Although changes might naturally occur because of mutations on the genome, the stable conditions of the environment do not exert changes on the living organisms, and most importantly, the eventually changes that mutations provide, will be cancelled by the same stable environment conditions. So, the given species might remain the same for millions of years.
