Final answer:
The most suitable organizational structure for an informative essay about how birds are categorized into species is DE (Definition and Explanation).
Step-by-step explanation:
The most suitable organizational structure for an informative essay about how birds are categorized into species would be DE, which stands for Definition and Explanation.
In this structure, you would first define the concept of bird species and then explain the criteria used to categorize birds into different species.
For example, you could start by briefly defining the term 'species' and then provide information about the characteristics and genetic differences that determine bird species.
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