选择题：18.期望值的实质是以( )为权数的各方案实施后的各种可能性出现结果的加权平均。(本题2.0分)A.

题目内容：

18.期望值的实质是以( )为权数的各方案实施后的各种可能性出现结果的加权平均。(本题2.0分)
A. 各方案占用资金比
B. 各方案产出比
C. 概率
D. 各方案利润比

参考答案：

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