6. [6 points]. 2 -8 3 4 Let X= Y= where v is a real constant. For which Value( s) 3 4 -6 v2 of v ( if any) do X and Y commute (A) 0 (B) 1 (C) + 1 (D) +3 ( E) numbers that are not in A - D (F) no values of v