Concept:A matrix M is skew-symmetric if MT=−M.Here we check this property for AB−BA.Explanation:Let C=AB−BA.To test symmetry, compare CT with C.Now, CT=(AB−BA)T.Use (X−Y)T=XT−YT and (XY)T=YTXT.So, CT=BTAT−ATBT.Since A and B are skew-symmetric, AT=−A and BT=−B.Substituting these gives CT=(−B)(−A)−(−A)(−B).Hence, CT=BA−AB.Thus, CT=−(AB−BA)=−C.This satisfies the condition CT=−C.Therefore, AB−BA is skew-symmetric.Answer:AB−BA is a skew-symmetric matrix.So, the correct option is B.