What is 'to_block'

I am struggling to get balance from this code.

const balances = await Moralis.Web3API.account.getTokenBalances(); const options = { chain: 'bsc', address: "0x...", to_block: "10253391" } const balances = await Moralis.Web3API.account.getTokenBalances(options);

what is to_block? you can check the attachment for my output.

That should mean if you want historical data from a specific block number.