Which of the Following Taxonomic Groups Is the Most Successful

Multiple Choice

Which of the following taxonomic groups is the most successful?

A) Fungi are the most successful, based on their ability to digest cellulose, the most common organic compound on Earth.
B) Bony fishes are the most successful, based on their high species diversity (almost as many as all other vertebrates combined) .
C) Mammals are the most successful, based on their complex mode of reproduction.
D) All extant species are successful, based on their continuing existence.