pat is a cash basis taxpayer who had $1000 of state income tax withheld from her salary in year 1. in addition,during year 1 she received a refund of year 0 state income taxes of $250. during year 1, pat also made estimated state income tax payments of $600. for year 1, pat's state income tax deduction is

a 750

b 1350

c 1000

d 1600

please explain