Assuming the momentum effect in stock returns is driven entirely by risk rather than mispricing, which would you expect to be true? The difference between average returns of winners and losers would: A$.$ be unchanged after the effect is widely publicized B$.$ decrease after the effect is widely publicized C$.$ increase after the effect is widely publicized D$.$ decrease after the effect is initially publicized, then return to its pre$-$publication value E$.$ increase after the effect is initially publicized, then return to its pre$-$publication value