The important reasons for constructing a policy statement would be option D. Choices A and B as investor's realistic decisions and measuring the manager's performance both are important and can be done by this.
The investment policy statement is a planning and communication document that
So, it will help the investment process to an investor to identify and make decisions on setting realistic goals. This also makes a standard or scale to which the portfolio manager can be judged for his performance evaluation.
Thus, the correct answer is - option D. choices A and B.
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