A ray of light is incident on a parallel slab of thickness t and refractive index n. If the angle of incident `theta` is small, then the displacement in the incident and emergent ray will be:
| A. |
`(t theta(n-1))/n` |
 |
| B. |
`(t theta)/n` |
| C. |
`(t theta n)/(n-1)` |
| D. |
none |