Tourave observed the cumulative abnormal returns graphed below surrounding the announcement of a new CEO for all publicly traded forms in the US from 1990 to 2020. The average CAR is plotted relative to the event date (0 on the figure). Chart A uses the CAPM to calculate expected returns Chart Buses the Fama-French 3-factor Model to calculate expected returns. Based on this evidence what can we conclude about market efficiency Chart A Chart B 4.00% 5.00% 3.00% 4.00% 2.00% 3.0096 1.00% 2.00% 1.00% -12 -8 -0.00% -4 0 4 8 00 12 -12 0.00% -4 0 -8 4 8 12 Looking at Chart A, we can conclude that the market is definitely efficient, because there is no change in CAR after the event O Looking at Chart B, we can conclude that the market is definitely inefficient, because the CAR continues to increase after the event We can conclude nothing about efficiency because of the joint-hypothesis problem o We can conclude both a and b, are true