Answer:
The correct option is d) mammals
Step-by-step explanation:
Studies made by scientists have shown that mammals are nor able to evolve fast enough as compared to other groups of animals. As a result, mammals tend to become more extinct as compared to organisms of the groups. Many mass extinctions of mammal organisms have been recorded over the past 400 years. The mammalian organisms possess little biodiversity in them as compared to organisms of the other phyla.