Among the options provided, primates have the fewest number of species, with around 500 known species. In comparison, birds number roughly 10,000 species, mammals over 6,500, and fungi possibly range between 2.2 to 3.8 million species. Therefore, the answer is B. primates. ;
Among the categories provided, primates contain the fewest number of species, with about 500 recognized species. In contrast, birds have around 10,000 species, mammals over 6,500, and fungi potentially range from 2.2 to 3.8 million species. Therefore, the answer is B. primates.
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