==> In the original condition, there is 1 variable (m) and in order to match the number of variables to the number of equations, there must be 1 equation. Since there is 1 for con 1) and 1 for con 2), D is most likely to be the answer.

For con 1), from [m]=1, it is unique and sufficient.

For con 2), from -1<m<1, you get [0]=0, but from [0.1]=-1, it is not unique and not sufficient.

Therefore, the answer is A.

Answer: A

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