Why do companies use a predetermined overhead rate to assign overhead to products rather than using actual overhead cost?

a. Because overhead costs are estimates, whereas predetermined rate is exact.

b. Because actual overhead costs are paid regularly, whereas products flow through the production process only sporadically.

c. Because actual overhead costs are known at the beginning of the period, whereas the predetermined overhead rate is not known until the end of the period.

d. Because actual overhead costs are paid sporadically, whereas products flow through the production process regularly.