Answer:
79 characters
Explanation:
The programming language is not stated, but a little search online shows the question is about python programming language
Literally, identifiers are the names given to variables, arrays and functions.
In most programming languages (e.g. python), identifiers are case-sensitive.
i.e. Abc is a different identifier when compared to abc.
Having said that, python allows up to 79 characters to name an identifier.
Meaning that, the length of a variable name (or array, or function, etc.) can be up to 79 characters, and it cannot exceed 79 characters.