An annulus is the region between two concentric circles. The concentric circles in the figure have radii \(b\) and \(c\), with \(b>c\). Let \(OX\) be a radius of the larger circle, let \(XZ\) be tangent to the smaller circle at \(Z\), and let \(OY\) be the radius of the larger circle that contains \(Z\). Let \(a=XZ\), \(d=YZ\), and \(e=XY\). What is the area of the annulus?

\(\mathrm{(A) \ } \pi a^2 \qquad \mathrm{(B) \ } \pi b^2 \qquad \mathrm{(C) \ } \pi c^2 \qquad \mathrm{(D) \ } \pi d^2 \qquad \mathrm{(E) \ } \pi e^2\)

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