Light of wavelength\[\lambda =5000\,\,{AA}\]falls normally on a narrow slit. A screen placed at a distance of 1 m from the slit and perpendicular to the direction of light. The first minima of the diffraction pattern is situated at 5 mm from the centre of central maximum. The width of the slit is

• A. 0.1 mm                                   
• B. 1.0 mm
• C. 0.5 mm                                   
• D. 0.2 mm