For a two port network to be reciprocal, its Scattering parameters must satisfy the following condition, for i = 1, 2 ; j = 1, 2

A

$$S_{ij} = S_{ji} (i \neq j)$$

B

$$S_{ij} = S_{ji} (i = j)$$

C

$$S_{ij} = \frac{1}{S_{ji}} (i \neq j)$$

D

$$S_{ij} = S_{ji}^* (i = j)$$