若椭圆\(C:\frac{{{x^2}}}{9} + \frac{{{y^2}}}{{m + 9}} = 1\)的离心率是\(\frac{1}{2}\)，则实数

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若椭圆\(C:\frac{{{x^2}}}{9} + \frac{{{y^2}}}{{m + 9}} = 1\)的离心率是\(\frac{1}{2}\)，则实数\(m\)的值等于\((\quad )\)

A.\( - \frac{9}{4}\)

B.\(\frac{1}{4}\)

C.\( - \frac{9}{4}\)或3

D.\(\frac{1}{4}\)或3

参考答案：C