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Jarrod and Lisa filed a joint tax return in 2017. Their AGI was $85,000, and their itemized deductions were $13,700, which included $4,000 in state income tax. In 2018, they received a $1,800 refund of state income taxes they paid in 2017. The standard deduction for married filing jointly in 2017 was $12,700. Under the tax benefit rule, the amount of the stat income tax refund that is included in gross income in 2018 is A. $4,000. B. $1,800. C. $2,000. D. $1,000. E. $0