On December 1.Simpson Marketing Company received 7,800 from a customer for a 2-month marketing plan to be completed January 31 of the following year. The cash receipt was recorded as unearned revenue. The adjusting entry for the year ended December 31 would include: Multiple Choice a debit to Services Revenue for 7,800 a debit to Unearned Revenue for 3,900. a debit to Services Revenue for 5,200 a credit to Unearned Revenue for 2,600 a credit to Services Revenue for 5,200.

To determine the correct adjusting entry for the year ended December 31, we need to recognize the revenue earned during December.The total amount received was 3,900.The adjusting entry would involve:- Debiting Unearned Revenue to decrease the liability (since part of it has now been earned).- Crediting Services Revenue to recognize the revenue earned.Thus, the adjusting entry for December 31 would include:A debit to Unearned Revenue for 3,900.Therefore, the correct choice from the options given is:**a debit to Unearned Revenue for $3,900.**