Answer: c is less than zero (third choice)
The parent nth root function (n is some odd number) will look like this sideways S shape, or look like a rotated cubic curve shape. The vertical flat part of the nth root is normally at (0,0); however, it has been shifted down and to the left. Because it has been shifted down, this means c must be negative. The 'c' handles the up and down shifting, depending whether its positive or negative.