___ can't be used as an identifier in java.*1 pointInbuilt class namesInbuilt method namesKeywordsAll of the above

Break Down the Problem

1. Identify what constitutes an identifier in Java.
2. Understand what is prohibited from being used as an identifier.

Relevant Concepts

1. Identifier in Java: An identifier is a name used for variables, methods, classes, etc.
2. Rules for Identifiers:
   • Identifiers cannot be a Java keyword (reserved words).
   • Identifiers should not be the same as inbuilt class names or method names to avoid conflicts or confusion.

Analysis and Detail

1. Inbuilt Class Names: Names of built-in Java classes (like String, System, etc.) cannot be used as identifiers because it would cause ambiguity in the code.
2. Inbuilt Method Names: Similarly, names of built-in methods (like println, size, etc.) are also inappropriate for usage as identifiers for the same reason.
3. Keywords: Java keywords (like int, class, void, etc.) are strictly reserved and cannot be used as identifiers.

Verify and Summarize

All the options provided (inbuilt class names, inbuilt method names, and keywords) are inappropriate for use as identifiers in Java.

Final Answer

All of the above