Correct option is D
Ball bearings typically fail due to mechanisms such as spalling (surface fatigue), brinelling (indentation), and creep (relative movement between ring and shaft/housing). These are well-known failure modes associated with rolling contact and load conditions.
However, bending is not a failure mode of ball bearings. Bending is generally related to shafts or structural members, not to the rolling elements or races of a bearing. Bearings are designed to handle radial and axial loads, but failure occurs due to surface damage, wear, or improper lubrication rather than bending.
