Mahabharata 12.175.8

कथं सृष्टानि भूतानि कथं वर्णविभक्तयःशौचाशौचं कथं तेषां धर्माधर्मावथो कथम्

kathaṃ sṛṣṭāni bhūtāni kathaṃ varṇavibhaktayaḥśaucāśaucaṃ kathaṃ teṣāṃ dharmādharmāvatho katham

Our plain-language meaning of this verse is waiting for scholar review.