For $50 a month, Rawl Co. visits its customers premises and performs insect control services. If customers experience problems between regularly scheduled visits, Rawl makes service calls at no additional charge. Instead of paying monthly, customers may pay an annual fee of $540 in advance. For a customer who pays the annual fee in advance, Rawl should recognize the related revenue

Evenly over the contract year as the services are performed.

At the end of the contract year after all of the services have been performed.

When the cash is collected.

At the end of the fiscal year.

(Give the proper answer with theory)