According to the theorem of parallel axes, the moment of inertia of a body about any axis is given by $I = I_{cm} + md^2$, where $I_{cm}$ is the moment of inertia about a parallel axis passing through the center of mass, $m$ is the mass of the body, and $d$ is the perpendicular distance between the two axes. The moment of inertia will be maximum about an axis for which the distance '$d$' from the center of mass is maximum. In the context of the standard diagram for this question, point B is situated at the maximum distance from the center of the disc (usually at the rim). Therefore, the moment of inertia is maximum about an axis perpendicular to the disc and passing through point B.