Which of these is incorrectly matched?

The correct answer is Option (3) → Mandasor - Inscription of Ashoka

Option 1- V.S. Sukthankar - Critical edition of the Mahabharata (Correct)
Option 2- Manusmriti - Laid down duties of the Chandalas (Correct)
Option 3- Mandasor - Inscription of Ashoka (Incorrect)
Option 4- Rig Veda - Concern with Patriliny (Correct)

The Mandasor inscription is not about Asoka. It is about silk weavers who migrated to Mandasor.

We seldom come across documents that record the histories of these groups. But there are exceptions. One interesting stone inscription (c. fifth century CE), found in Mandasor (Madhya Pradesh), records the history of a guild of silk weavers who originally lived in Lata (Gujarat), from where they migrated to Mandasor, then known as Dashapura. It states that they undertook the difficult journey along with their children and kinfolk, as they had heard about the greatness of the local king, and wanted to settle in his kingdom.