he correct answerWhich of the following variable declaration would NOT compile in a java program?Optionsint var;int var1;int VAR;int 1_var;int var_1;

1. Break Down the Problem

We need to analyze the variable declarations in Java and determine which one of them is invalid based on the rules of naming conventions for variables.

2. Relevant Concepts

In Java, variable names must:

1. Start with a letter (a-z, A-Z), underscore (_), or dollar sign ($).
2. Subsequent characters can be letters, digits (0-9), underscores, or dollar signs.
3. Cannot start with a digit.

3. Analysis and Detail

Let’s analyze each option:

1. int var; – Valid. It starts with a letter.
2. int var1; – Valid. It starts with a letter and contains letters and a digit.
3. int VAR; – Valid. It starts with a letter; case sensitivity allows differentiating names.
4. int 1_var; – Invalid. It starts with a digit, which is not allowed.
5. int var_1; – Valid. It starts with a letter and contains an underscore and a digit.

4. Verify and Summarize

The only variable declaration that does not conform to Java's variable naming rules is int 1_var;, as it starts with the digit '1'.

Final Answer

int 1_var; is the variable declaration that would NOT compile in a Java program.