The most abundant group of organisms in the animal kingdom is
- mammalia
- aves
- annelida
-
insecta
The correct answer is: D
Explanation
Insects are the most abundant group of living creatures on earth with up to 30 million estimated species of insect found worldwide.
Insects can be found in all ranges of environments even (but limited) in the oceans and rivers. Insects feed on other, smaller insects and decaying leaf and plant matter.
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