6.12 A total of 12 pieces of chocolate of exactly the same size, each piece can be divided into at most two smaller pieces (which may not be equal). If these 12 pieces of chocolate can be evenly distributed among $n$ students, then $n$ can be ( ).
(A) 26
(B) 23
(C) 17
(D) 15
6. (D).
12 chocolate bars are evenly distributed among 15 students, each should receive $\frac{4}{5}$ of a bar. Therefore, each chocolate bar can be divided into two smaller pieces in a $4:1$ ratio, with 12 students each getting 1 larger piece, and the other 3 students each getting 4 smaller pieces.