At the end of the year, Rollin Company had applied a total of $800,000 to its manufactured products, however its actual overhead incurred during the year amounted to $825,000. Rollin has:

a. underapplied its manufacturing overhead to its products by $25,000

b. overapplied its manufacturing overhead to its products by $25,000

c. used an inappropriate method of overhead allocation for its products.

d. an obligation to replace its production manager