2 A: I'm going shopping. Can you come?

Step 1: Analyze the question: "I'm going shopping. Can you come?" This is an invitation to join an activity. Step 2: Evaluate the options for a suitable response. Step 3: Option (c) "I'm sorry, I can't come. I'm busy." is a polite way to decline the invitation.

I'm sorry, I can't come. I'm busy.