Which of the quadratic functions has the narrowest graph?

y = -4x^2
y = 1/2x^2
y = -2x^2
y = 1/7x^2

The quadratic function with the narrowest graph is the one with the largest coefficient in front of the x^2 term, as this value determines the "steepness" of the graph. Therefore, out of the given options, y = -4x^2 has the narrowest graph.