Which of the Following Statements Is Correct? an Individual Worker's

Which of the following statements is correct? An individual worker's labor supply curve

A) can never be backward sloping.
B) slopes backward if that person responds to a higher wage by taking fewer hours of leisure per week.
C) slopes backward if that person responds to a higher opportunity cost of leisure by working fewer hours per week.
D) slopes upward if that person works the same number of hours per week, regardless of the opportunity cost of leisure.