Answer:
c. $25,450.
Step-by-step explanation:
All the expenses and asset accounts have debit balances so, the total debit value of unadjusted trial balance can be calculated by adding all the expense and asset account balances.
 $
Land 4,800 
Equipment 5,900 
Accounts receivable 5,500 
Cash 1,800 
Notes receivable matures 2016 1,300 
Prepaid Insurance 450 
Insurance expense 450 
Rent expense 1,450
Salaries and Wages expense  3,800 
Total Debit Balances 25,450 
Following accounts are equity and liability accounts, these accounts are credit in nature.
Service revenue 6,800 
Accounts payable 700 
Common stock 5,000 
Notes payable, due 2018 5,000 
Retained earnings, January 1, 2015 7,950