Correct Answer - B
Lateral shift `y=(tsin(i-r))/(cosr)=tsini-tcosi(sinr)/(cosr)`
`(1xxsini=nsinr)`
`=tsini-tcost(sini//n)/(sqrt(1-(sin^2i)/(n^2)))=tsini[1-(cosi)/(sqrt(n^2-sin^2i))]`
When i is small, `sin^2 i` is negligible, `cos i=1`, `sin i=sin theta=theta`
`=ttheta(1-1/n)=(ttheta(n-1))/(n)`