What is the main advantage of construction a factor portfolio using a multifactor model compared to the hedge portfolio approach? a. The multifactor model can allow investors to control for the effect of other factors and construct the pure factor mimicking portfolio b. The multifactor model is simpler to apply compared to the hedged portfolio approach c. The hedged portfolio approach is more consistent with the APT d. The hedged portfolio approach can take into account of the information of all stocks in the universe