A study has been conducted to determine if one of the departments in Parry Company should be discontinued. The contribution margin in the department is $50,000 per year. Fixed expenses charged to the department are $65,000 per year. It is estimated that $40,000 of these fixed expenses could be eliminated if the department is discontinued. These data indicate that if the department is discontinued, the company's overall net operating income would:
a. Decrease by $25,000 per year
b. Increase by $25,000 per year
c. Decrease by $10,000 per year
d. Increase by $10,000 per year