(a) The poem supports noble ideal of equality (or equality of all castes or human beings). As far as body is concerned it is unclean (or dirty) of everyone. There is a soul in everybody (of every caste). Soul is untained it is faith of Brahmins or people of upper caste. She believes that impurity of the body is born within it since the time of birth and last till it goes to tomb. She is asking the powerful social group by which the ritual the body can be pure. Everybody comes out or born from a bloody warm. This is the law of nature or glory of God. In fact, defilement prevails within body. It is polluted from within. No one is low or high. All are equal. All are human beings.
(b) Yes. Marginalised community in our locality is the scheduled caste community. Now frame a poem or song or draw a poster, etc. to express your feelings as a member of this community.
Hints: A Poster
An SC member wants to enter a Hindu Temple.
The Priest asks him not to do so.
Visitors to the temple belonging to Hindu powerful people beat the SC member and throw him away out of the gate of the temple.