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The outputs of four systems $(S_{1}, S_{2}, S_{3},$ and $\text{S}_{4})$ corresponding to the input signal $\sin(t),$ for all time $t,$ are shown in the figure.

Based on the given information, which of the four systems is/are definitely $\text{NOT LTI}$ (linear and time-invariant)?

1. $S_{1}$
2. $S_{2}$
3. $S_{3}$
4. $S_{4}$