Which chain is BNB in MetaMask?

Excuse me, could you please clarify for me which blockchain network is BNB associated with in MetaMask? I'm trying to set up my wallet to hold some Binance Coin, but I'm not entirely sure which chain to select. I've heard about different networks like Ethereum, BSC, and others, but I'm not sure which one applies to BNB specifically within MetaMask. Could you guide me through this process? It would be greatly appreciated.