Choice "B" is correct. Total fund balance equals total assets of $1,000,000 less total liabilities of $600,000, or $400,000. Since appropriations do not lapse at year-end, the $100,000 budgetary control (open purchase orders), must be reported as part of the committed or assigned portion of fund balance. As a result, the unassigned fund balance is the difference, $400,000 - $100,000, or $300,000.Choice "d" is incorrect. The $200,000 cash is not used to determine the unassigned fund balance.Choice "c" is incorrect. The $400,000 is the total fund balance. The $100,000 Encumbrance commitment is part of this total.Choice "a" is incorrect. The $100,000 included in either committed or assigned fund balance is subtracted from the total fund balance, not added to it.