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Answer:
D. f(x) = x - 4
Step-by-step explanation:
If you plug in the x values for the expression x - 4:
3 - 4 = -1
4 - 4 = 0
5 - 4 = 1
6 - 4 = 2
This means that the function rule is f(x) = x - 4
Hope this helps :)