What chain does Coinbase use for AVAX?

Could you please clarify which blockchain network Coinbase utilizes for transactions involving AVAX, the native token of Avalanche? As Avalanche operates on its own unique consensus mechanism and blockchain architecture, it's essential to understand the specific chain Coinbase employs for facilitating AVAX trades and transfers. This information is crucial for users looking to navigate the platform and ensure seamless transactions with AVAX.