CEMC Cayley, 2004

Geometry Difficulty 2.0 Junior Find the answer Canada

In the diagram, $O$ is the centre of each circle. The circumferences of the circles are $24\pi$ and $14\pi$ . $B$ is a point on the outer circle and $OB$ intersects the inner circle at $A$ . The length of $AB$ is

(A) $\sqrt{10}$ (B) $5$ (C) $7$ (D) $10\pi$ (E) $3$

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