Two short magnets of equal dipole moments M are fastened perpendicularly at their centre (figure). The magnitude of the magnetic field at a distance d from the centre on the bisector of the right angle is

• A. \[\frac{{{\mu }_{0}}}{4\pi }\frac{M}{{{d}^{3}}}\]
• B. \[\frac{{{\mu }_{0}}}{4\pi }\frac{M\sqrt{2}}{{{d}^{3}}}\]
• C.   Weight of a standard kilogram mass
• D.  \[\frac{{{\mu }_{0}}}{4\pi }\frac{2M}{{{d}^{3}}}\]