Which best describes a dichotomous key? each step has two choices. each step can have any number of choices. each step describes two possible inferences. each step is based on genetic traits.

Answer; 
The statement that best describes a dichotomous key is that each step has two choices. 

Explanation; 
Dichotomous key is a tool that allows users to determine the identity of objects in the natural world. Most often it is used in identifying plant and animal species based on their characteristics. The key contain a series of steps each with two choices that lead the user to the correct name of a given organisms. 

A dichotomous key is something in which "Each step has two choices". The secondary root is "dichotomy" which has a similar meaning. These are very useful for biologists.

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