The S matrix of a lossless line having length $$\frac{\lambda}{4}$$ is

A

$$\begin{bmatrix}1 & 0 \\0 & 1 \end{bmatrix}$$

B

$$\begin{bmatrix}1 & -1 \\-1 & 1 \end{bmatrix} $$

C

$$\begin{bmatrix}0 & j \\j & 0 \end{bmatrix} $$

D

None of these