Global Investment Performance Standards (GIPS), Were Intended to Accomplish Which

Global Investment Performance Standards (GIPS) , were intended to accomplish which of the following goals?

A) to assess the quality of services provided by money managers by looking at adjustments made to the content of their portfolios
B) to measure both unsystematic and systematic risk
C) to establish investment industry best practices for calculating and presenting investment performance that promote investor interests and instill investor confidence
D) to measure portfolio performance on the basis of return per unit of risk
E) to measure portfolio performance on the basis of historic average differential return per unit of historic variability of differential return