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11. Mostafa is a self-employed artist who operates a qualifying office in his home. Mostafa has $125,000 gross income from his practice and $105,000 of expenses directly related to the business, i.e., non-home office expenses. Mostafa's allocable home office expenses for mortgage interest expenses and property taxes are $12,000 and other home office expenses are $10,000. What is Mostafa's total allowable home office deduction? A) $9,000 B) $14,000 C) $20,000 D) $22,000