问题如下：
A manager has a mandate to be fully invested with a benchmark that is a blend of large-cap stocks and investment-grade bonds. Which of the following is not an indication that style drift has occurred? The manager:
选项：
A.initiates an allocation to small-cap stocks.
decreases investments in investment-grade corporate bonds.
increases allocation to cash in anticipation of a market decline.
解释：
B is correct.
In the normal course of business, the manager conforms to its style by reducing exposure to some class of investment grade bonds. Increasing allocation to cash and small-cap stocks is in violation of the mandate to be fully invested with equity exposure to large-cap stocks.
请问B选项为什么减少了investment bond的投资不算风格发生变化了呢？
