What does 'mobility' refer to?

'Mobility' fundamentally refers to the ability to move or be moved freely and easily. This concept encompasses various interpretations in different contexts, including physical movement, the movement of people, and even social or economic mobility. In essence, mobility is associated with flexibility, adaptability, and the capacity to change positions or locations as desired or required.

The other options represent ideas that directly contradict or limit the definition of mobility. A state of remaining still, a condition of being immobile, and the capacity to lift heavy objects do not align with the notion of movement or flexibility, which is central to the concept of mobility. These aspects emphasize a lack of movement or focus on specific physical abilities rather than the broader capability of movement itself.