The graph that consists of repeating vertical S-shaped curves is:
y = tan(x)
The tangent function has an S-shape, and it repeats every π radians, showing vertical asymptotes where the function is undefined. The sine function, y = sin(x), also has a wave-like shape but does not consist of S-shaped curves. The function y = x^3 is a cubic function and doesn't have the repeating pattern, and y = √(x-3) is not periodic and does not exhibit S-shaped curves.