关于无排卵型功血，其出血机制错误的是：（）
A．雌激素撤退型出血
B．雌激素突破型出血
C．凝血功能异常
D．无排卵
E．无孕激素分泌
参考答案：C
As we are busy these days, we might _________ this urgent work for the time being. [ ]
A. undertake
B. agree
C. undergo
D. charge
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