Which of the Following Statements Is FALSE

Which of the following statements is FALSE?

A) Because expected returns are not easy to estimate,each portfolio that is added to a multifactor model increases the difficulty of implementing the model.
B) The self-financing portfolio made from high minus low book-to-market stocks is called the high-minus-low (HML) portfolio.
C) The Fama-French-Carhart (FFC) factor specification was identified a little more than ten years ago.Although it is widely used in academic literature to measure risk,much debate persists about whether it really is a significant improvement over the CAPM.
D) A trading strategy that each year short sells portfolio S (small stocks) and uses this position to buy portfolio B (big stocks) has produced positive risk-adjusted returns historically.This self-financing portfolio is widely known as the small-minus-big (SMB) portfolio.