You can use the addition operator $(+)$ in several ways in JavaScript. However, you CANNOT use the addition operator to $\_\_\_\_\_.$a$.$combine the text string"Good morning, "with the value offirstNameb.perform arithmetic operations using the names of variables with integer valuesc.combine the text string"Your score is: "with the integer $20$ in displayed textd.add the integer $10$ and the string"$10"$to return the integer $20$