Which of the following dimension(s) can explain 'untouchability'?

Exclusion, humiliation-subordination and exploitation

It is important to emphasise that the three main dimensions of untouchability – namely, exclusion, humiliation-subordination and exploitation – are all equally important in defining the phenomenon. Although other (i.e., ‘touchable’) low castes are also subjected to subordination and exploitation to some degree, they do not suffer the extreme forms of exclusion reserved for ‘untouchables.’ Dalits experience forms of exclusion that are unique and not practised against other groups – for instance, being prohibited from sharing drinking water sources or participating in collective religious worship, social ceremonies and festivals. Moreover, untouchability is almost always associated with economic exploitation of various kinds, most commonly through the imposition of forced, unpaid (or under-paid) labour, or the confiscation of property. Finally, untouchability is a pan-Indian phenomenon, although its specific forms and intensity vary considerably across regions and socio-historical contexts