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If $s^{3}+3 s^{2}+4 s+A=0$, then all the roots of this equation are in the left half plane provided that

1. $\mathrm{A}>12$
2. $-3<\mathrm{A}<4$
3. $0<\mathrm{A}<12$
4. $5<\mathrm{A}<12$