The correct option is A There is only one (m, n) solution and n is negative.
Consider the ratio of coefficient of n's : 11
Ratio of coefficient of m's : 23
Since the ratio of coefficient of n's and m's are not equal. Therefore, the system will have a unique solution. Equate the LHS of the equations since RHS is n for both equations.
2m - 1 = 3m - 1
m = 0
Substitute in any equation, to get the value of n = -1.
Therefore, the correct answer is option A.