In the conversation between Bhrigu and Bharadwaj in the Epic Mahabharata, what does Bhrigu quote as the identity for difference in caste.

Skin color

The correct answer is Option 3: Skin color

The tradition of questioning:  When, in the Mahabharata, Bhrigu tells Bharadvaja that caste division relates to differences in physical attributes of different human beings, reflected in skin colour, Bharadvaja responds not only by pointing to the considerable variations in skin colour within every caste (‘if different colours indicate different castes, then all castes are mixed castes’), but also by the more profound questions: “We all seem to be affected by desire, anger, fear, sorrow, worry, hunger and labour; how do we have caste differences then?”

Note: This question is from pre rationalised NCERT.