Answer : 4. "Rishabhdev"
Explanation :

1. Jainism and Buddhism originated during the later Vedic period when the people were developing into Mahajanapadas.

2. Jainism was founded by Rishabhdev who was born in Ayodhya and his symbol was the bull.

Sl. No.          - Name                         -  Symbol         - Birthplace

1                Rishabhnath (Adinath)   Bull                    Ayodhya

2                Ajitnath                              Hathi                 Ayodhya                                           

22              Neminath                          Shankh               Dwarka

23            Parshvanath                       snake                  Kashi

24           Mahavir Singh                   Sher                 Kshatriyakund