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A $1$-to-$8$ demultiplexer with data input $D_{in}$ , address inputs $S_{0}, S_{1}, S_{2}$ (with $S_{0}$ as the LSB) and $\overline{Y_{0}}$ to $\overline{Y_{7}}$ as the eight demultiplexed outputs, is to be designed using two $2$-to-$4$ decoders (with enable input $\overline{E}$ and address inputs $A_{0}$ and $A_{1}$) as shown in the figure. $D_{in} , S_{0}, S_{1}$ and $S_{2}$ are to be connected to $P, Q, R$ and $S,$ but not necessarily in this order. The respective input connections to $P, Q, R,$ and $S$ terminals should be

1. $S_{2}, D_{in}, S_{0}, S_{1}$
2. $S_{1}, D_{in}, S_{0}, S_{2}$
3. $D_{in}, S_{0}, S_{1}, S_{2}$
4. $D_{in}, S_{2}, S_{0}, S_{1}$