Choose the incorrect statement.

(a) In Young's double slit experiment, the fringe width is given by $\beta=\frac{\lambda D}{d} \Rightarrow \beta \propto \frac{1}{d}$ So, if width between two slit $(d)$ increases, the fringe width reduces. (b) In diffraction due to single slit, the path difference between rays reaching centre of screen is zero, so its intensity at centre is maximum i.e., bright fringe is observed at centre. (c) The resolving power of microscope is $=\frac{1}{d_{\min }}=\frac{2 n \sin \beta}{1.22 \lambda}$ So, it is the reciprocal of the minimum separation $\left(d_{\min }\right)$ of two points seen as distinct. (d) The polarisation is possible only in those waves, that have vibrations in different direction, which is in case of transverse waves. Hence, only statement given in option (c) is incorrect.