In a Young's double slit experiment with light of wavelength \[\beta \], fringe pattern on the screen has fringe width\[\beta \]. When two thin transparent glass (refractive index u) plates of thickness\[{{t}_{1}}\] and\[{{t}_{2}}\]\[({{t}_{1}}>{{t}_{2}})\] are placed in the path of the two beams respectively, the fringe pattern will shift by a distance

• A. \[\frac{\beta (\mu -1)}{\lambda }\left( \frac{{{t}_{1}}}{{{t}_{2}}} \right)\]
• B. \[\frac{\mu \beta }{\lambda }\frac{{{t}_{1}}}{{{t}_{2}}}\]
• C. \[\frac{\beta (\mu -1)}{\lambda }({{t}_{1}}-{{t}_{2}})\]
• D. \[(\mu -1)\frac{\lambda }{\beta }({{t}_{1}}+{{t}_{2}})\]