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已知偶函数 $y=f(x)$ 满足 $\cos x \cdot f^{\prime}(x)-\sin x \cdot f(x)>0$ 对 $x \in\left(0, \frac{\pi}{2}\right)$ 恒成立,下列正确的是()
A. $\sqrt{2} f\left(\frac{\pi}{4}\right) < f\left(\frac{\pi}{3}\right)$     B. $f\left(\frac{\pi}{4}\right) < \frac{\sqrt{6}}{2} f\left(-\frac{\pi}{6}\right)$     C. $f\left(\frac{\pi}{6}\right) < \frac{\sqrt{3}}{3} f\left(-\frac{\pi}{3}\right)$     D. $\sqrt{2} f(0)>f\left(-\frac{\pi}{4}\right)$         
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