For all functions of the form f(x) = ax2 + bx + c, which is true when b = 0?

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1

For all functions of the form f(x) = ax2 + bx + c, which is true when b = 0?
a. The graph will always have zero x-intercepts.
b. The function will always have a minimum.
c. The y-intercept will always be the vertex.
d. The axis of symmetry will always be positive.