What chain is ondo on?

Could you please clarify for me which blockchain network Ondo is operating on? I'm curious to know if it's based on a popular and established chain like Ethereum or if it's utilizing a newer or less commonly used blockchain technology. Additionally, could you provide any insights into the reasons why Ondo chose this particular chain? Is it due to scalability, security, cost-efficiency, or perhaps a combination of these factors? I'm interested in understanding the technological decisions behind Ondo's blockchain integration. Thank you for your assistance in answering this question.