none of them. its Yamoshi.
Yamoshi is an ancient Saiyan first officially mentioned in an interview with Dragon Ball creator Akira Toriyama. According to Toriyama, Yamoshi lived long before the events of Dragon Ball and existed during a period when Planet Vegeta was not yet ruled by Saiyans. Despite being born into a warrior race known for violence, Yamoshi possessed a righteous heart.
Toriyama explained that Yamoshi and five allies started a rebellion against evil Saiyans. During the conflict, Yamoshi became a Super Saiyan for the first time after being cornered in battle. His transformation and overwhelming fighting style surprised the other Saiyans, creating the foundation for the legendary Super Saiyan myth that would later spread across the universe.
Based on Toriyama’s explanation, Yamoshi was clearly the first known Saiyan to transform into a Super Saiyan. His battle against evil Saiyans created the original legend feared by figures like Frieza and referenced throughout DBZ.