Step 1: Understanding the Task
The task is to add the correct question tag to the end of the statement.
Step 2: Applying the Rules of Question Tags
The main rule for question tags is:
If the main statement is negative, the question tag is positive.
If the main statement is positive, the question tag is negative.
The tag uses the same auxiliary verb (or a form of 'do') as the main statement, and the same subject pronoun.
Step 3: Detailed Explanation
The main statement is "You aren't busy...". The word "aren't" (are not) makes the statement negative.
Therefore, the question tag must be positive.
The auxiliary verb in the statement is "are". The positive form is "are".
The subject pronoun is "you".
Combining the positive auxiliary verb and the pronoun gives the tag: "are you?".
Step 4: Final Answer
The correct question tag for the negative statement "You aren't busy" is the positive tag "Are you?". Therefore, option (B) is the correct answer.