I am looking for help with this general accounting question using proper accounting standards.

At the beginning of the year, manufacturing overhead for the year was estimated to be $432,000. At the end of the year, actual direct labor-hours for the year were 36,500 hours, the actual manufacturing overhead for the year was $418,600, and manufacturing overhead for the year was overapplied by $21,900. If the predetermined overhead rate is based on direct labor-hours, then the estimated direct labor-hours at the beginning of the year used in the predetermined overhead rate must have been: a. 33,200 direct labor-hours b. 35,900 direct labor-hours c. 36,000 direct labor-hours d. 36,500 direct labor-hours