Observation 1 = 12, 2 + 3 + 4 = 32, 3 + 4 + 5 + 6 + 7 = 52 & nbsp; the general conclusion is () A. 1+2… +n=（2n-1）2（n∈N*）B. n+（n+1）+… +（3n-2）=（2n-1）2（n∈N*）C. n+（n+1）+… +（2n-1）=（2n-1）2（n∈N*）D. 1+2… +n=（3n-1）2（n∈N*）

Observation 1 = 12, 2 + 3 + 4 = 32, 3 + 4 + 5 + 6 + 7 = 52 & nbsp; the general conclusion is () A. 1+2… +n=（2n-1）2（n∈N*）B. n+（n+1）+… +（3n-2）=（2n-1）2（n∈N*）C. n+（n+1）+… +（2n-1）=（2n-1）2（n∈N*）D. 1+2… +n=（3n-1）2（n∈N*）

From 1 = 12 = (2 × 1-1) 2; 2 + 3 + 4 = 32 = (2 × 2-1) 2; 3 + 4 + 5 + 6 + 7 = 52 = (2 × 3-1) 2; 4 + 5 + 6 + 7 + 8 + 9 + 10 = 72 = (2 × 4-1) 2 From the above formula, it is concluded that: the first term on the left of the nth equation is n, and then add 1 in turn, there are 2N-1 terms, and the right side of the equation is the square of 2N-1