Please help, ty!

The vertex of this parabola is  at the origin  = (0,0)

f(x)  =  (x - 1)^2    has a vertex  of  (1, 0)....so "A" is not correct

f(x)  = x^2  + 1      has a vertex  of  (0, 1).....so  "B" is not correct

f(x)   =  x - 1  is the graph of a line.....so....."D"  isn't correct, either

So....by default...."C"  must be correct

Verify this for yourself here, RP :

https://www.desmos.com/calculator/vgibuvxuhw