about the return value of get_currency_balance

[Albert-Gao]

Version of EOSJS
22.1.0

I am using get_currency_balance to retrieve a smart contract build on top of UX network.

blockChain.getCurrencyBalance([
              EDNAInfo.tokenContract,
              accountName,
              EDNAInfo.symbol,
])

Everything works fine, but the result is an array contain 1 result. for example : [111.0000 ABCDE]

1. Why is it an array, is this the total available token for the accountName?
2. When there are more than 1 result, what are they?

Thanks, tried to find the documentation, but can not find any information.