Will 1, 2 If the nine numbers are divided into three groups averagely, the probability that the three numbers in each group can form an arithmetic sequence is () A. 156B. 170C. 1336D. 1420

The nine numbers are divided into three groups, a total of c39c36c33a33 groups, in which the three numbers of each group are in arithmetic sequence, including {(1,2,3), (4,5,6), (7,8,9)}, {(1,2,3), (4,6,8), (5,7,9)}, {(1,3,5), (2,4,6), (7,8,9)}, {(1,4,7), (2,5,8), (3,6,9)}, {(1,5,9), (2,3,4) ）(6,7,8)}, a total of 5 groups. The calculated probability is 58 × 7 × 5 = 156

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