2. Around a table are sitting 4 people, each of whom can either be a knight (who always tells the truth) or a knave (who always lies). Each of those present states: "Of the other three people sitting at this table with me, the knaves are exactly two." What is the total number of knaves sitting at the table?
(A) none
(B) 
definitely 2
(C) definitely all 4
(D) definitely 1
(E) the information provided is not sufficient to determine it