问题如下：
1.The core-plus fixed-income composite includes a portfolio managed on behalf of the Avonfield Academy endowment fund. The trustees of Avonfield inform Belltower in writing that, due to a change in investment policy, the endowment fund is no longer permitted to hold below-investment-grade securities. Belltower determines that henceforth the Avonfield portfolio should be included in the core fixed-income composite, rather than the core-plus fixed-income composite. The historical record of the portfolio must be:
选项：
A. included in both composites.
B. kept in the core-plus fixed income composite.
C. excluded from the core-plus fixed income composite.
解释：
B is correct.
Provision I.3.A.7 states, "Portfolios must not be switched from one composite to another unless documented changes to a portfolio’s investment mandate, objective, or strategy or the redefinition of the composite make it appropriate. The historical performance of the portfolio must remain with the original composite." (Emphasis added.) (See Section 3.9 of the reading.)
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