What can be said regarding variable names in Java?

• A. They can start with any letter or number.
• B. They must start with a letter, $ or _.
• C. They cannot start with an underscore.
• D. They are case-insensitive in Java.

Answer: (B)

In Java, variable names (also known as identifiers) have specific rules regarding their formation. The choice indicating that variable names must start with a letter, dollar sign ($), or underscore (_) is correct because:

1. Starting Characters: Variable names must begin with a letter (either uppercase A-Z or lowercase a-z), a dollar sign ($), or an underscore (_). This rule is designed to allow some flexibility in naming while ensuring that identifiers are clearly distinguishable. Starting with a digit or any other character is not permitted since it could lead to confusion, especially in parsing and interpreting the code.

2. Subsequent Characters: After the initial character, variable names can include letters, digits (0-9), underscores, and dollar signs. This flexibility allows for meaningful names that reflect the purpose of the variable, enhancing code readability and maintainability.

3. Naming Conventions: While variable names can include special characters like the underscore and dollar sign, it's generally advisable to adhere to naming conventions for clarity. For example, using camelCase for variable names starting with a lowercase letter is a common practice in Java.

The other statements do not align with Java's syntax rules. For instance, variable names cannot start with a number,