CEMC Fermat, 2007

Algebra Difficulty 2.0 Junior Find the answer Canada

The graph of the function $y = ax^2 + bx + c$ is shown in the diagram. Which of the following must be positive?

(A) $a$ (B) $bc$ (C) $ab^2$ (D) $b-c$ (E) $c-a$

Figure for this problem

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