问题如下：
Which one of the followings is most likely correct about the composite construction?
选项：
A. Composites can include the assets managed by the firm which is not actual.
B. Composites can link performance of model portfolios with the actual performance.
C. All actual, fee-paying, discretionary portfolios must be included in at least one composite.
解释：
C is correct.
According to Composite Construction, composites must include only actual assets managed by the firm. And composites mustn't link performance of simulated or model portfolios with the actual performance.
选项 b 错在哪里?
