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Answer:
The above network can be considered as cascade connection of two networks $N_1$ and $N_2$.
The network $N_1$consists of $2 \Omega $ resistor , $2H$ inductor and $2F$ capacitor.
Applying KVL to mesh 1 of network $N_1$,
$V_1=\bigg(2+\dfrac{1}{2s}\bigg)I_1+\dfrac{1}{2s}I_2$.............................(1)
Applying KVL to mesh 2 ,
$V_2=\dfrac{1}{2s}I_1+\bigg(2s+\dfrac{1}{2s}\bigg)I_2$.............................(2)
From (2) we have
$I_1=2sV_2-(4s^2+1)I_2$..................................(3)
Substituting (3) in (1),
$V_1=\bigg(2+\dfrac{1}{2s}\bigg)\bigg[2sV_2-(4s^2+1)I_2\bigg]+\dfrac{1}{2s}I_2$
$V_1=(4s+1)V_2-(8s^2+2s+2)I_2$
On comparing with the ABCD paramter equation , we get
$ \begin{bmatrix} A_1 &B_1 \\[0.3em] C_1 & D_1 \\[0.3em] \end{bmatrix}= \begin{bmatrix} 4s+1 & 8s^2+2s+2 \\[0.3em] 2s & 4s^2+1 \\[0.3em] \end{bmatrix} $
The network $N_2$ consists of the parallel combination of $1F$ capacitor and $1 \Omega $ resistor,
Applying KVL to the mesh 1 ,
$V_1'=\dfrac{1}{s+1}I_1'+\dfrac{1}{s+1}I_2'$......................(4)
Applying KVL to mesh 2 ,
$V_2'=\dfrac{1}{s+1}I_1'+\dfrac{1}{s+1}I_2'$.......................(5)
From (5)
$I_1'=(s+1)V_2'-I_2'$...............................(6)
Also , $V_1'=V_2'$......................................(7)
Comparing (6) and (7) with ABCD paramter equations ,
$ \begin{bmatrix} A_2 &B_2 \\[0.3em] C_2 & D_2 \\[0.3em] \end{bmatrix}= \begin{bmatrix} 1 & 0 \\[0.3em] s+1 & 1 \\[0.3em] \end{bmatrix}$
Hence , overall ABCD parameters are
$ \begin{bmatrix} A &B \\[0.3em] C & D \\[0.3em] \end{bmatrix}= \begin{bmatrix} 4s+1 & 8s^2+2s+2 \\[0.3em] 2s & 4s^2+1 \\[0.3em] \end{bmatrix} \begin{bmatrix} 1 & 0 \\[0.3em] s+1 & 1 \\[0.3em] \end{bmatrix}$
$ \begin{bmatrix} A &B \\[0.3em] C & D \\[0.3em] \end{bmatrix}= \begin{bmatrix} 8s^3+10s^2+8s+3 & 8s^2+2s+2 \\[0.3em] 4s^3+4s^2+3s+1 & 4s^2+1 \\[0.3em] \end{bmatrix} $