The amount of money an employee earns monthly before taxes, in dollars, after selling n products is $1,300 + $300n. Which statement is correct? A. For every product sold, the employee's earnings increase by $1,300. B. For every product sold, the employee's earnings increase by $1,000. C. For every product sold, the employee's earnings increase by $1,600. D. For every product sold, the employee's earnings increase by $300.