Mahabharata 3.177.26

युधिष्ठिर उवाच · yudhiṣṭhira uvāca

जातिरत्र महासर्प मनुष्यत्वे महामतेसंकरात्सर्ववर्णानां दुष्परीक्ष्येति मे मतिः

jātiratra mahāsarpa manuṣyatve mahāmatesaṃkarātsarvavarṇānāṃ duṣparīkṣyeti me matiḥ

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