The correct answer is option 1, which states that statements 1 and 2 are correct.

The Jains believe that Mahavira, the twenty-fourth Tirthankara, had twenty-three predecessors. This means that there were twenty-three spiritual leaders who came before Mahavira and contributed to the Jain philosophy and teachings.

Parshvanatha is indeed considered the twenty-third Tirthankara in Jainism. He is believed to have lived in the prehistoric age, thousands of years before Mahavira. Parshvanatha is highly revered by Jains for his teachings on non-violence and asceticism.

Statement 3, however, is incorrect. Rishava is not the immediate successor of Mahavira. The immediate successor of Mahavira was Sudharma, who became the head of the Jain monastic order after Mahavira attained Nirvana (liberation from the cycle of birth and death).

So, the only correct statements among the given options are statements 1 and 2.