What should be the orientation of a magnetic dipole in a uniform magnetic field so that its potential energy is maximum?

Potential energy of a magnetic dipole in a uniform magnetic field $U=-MB\cos q$ clearly the potential energy is maximum when $\cos \theta =-1$ or $\theta =\pi$ That is, potential energy is maximum when magnetic dipole with its magnetic moment $\vec{M}$ is oriented opposite to the direction of magnetic field ( or angle between $\vec{M}$ and $\vec{\delta }$ is $180^o)$.