Which expression is equivalent to 17x − 8x + 2 and why?

2 − 9x, because (17x − 8x) + 2 = −9x + 2 = 2 − 9x

2 + 9x, because (17x − 8x) + 2 = 9x + 2 = 2 + 9x

11x, because 17x − 8x + 2 = 9x + 2 = 11x
7x, because 17x − 8x + 2 = 17x − 10x = 7x