Sheridan Company is in the business of selling annual subscriptions for its proprietary software. On October 1, Jasper sold 13 annual subscriptions for $210 each. Assuming Sheridan makes adjusting entries just once at the end of each year, its December 31 journal entry will include:

Select one: a. A debit to Revenue of $682.50 b. A credit to Unearned Revenue of $2730.00 c. A credit to Revenue of $2730.00 d. A debit to Unearned Revenue of $682.50