selecting all row of max value of a column
Your query will get the max value of I_COMDTY_ID with ANY combination of the other fields from the rows that satisfies your WHERE condition.

A better way to do that:

SELECT 
    t3.C_COMDTY_SHORT_DESC,
    t3.C_HS_CODE,
    t3.I_COMDTY_ID,
    I_COMDTY_ID
FROM
    ADM_COMMODITY_MASTER t3 
WHERE
    t3.C_HS_CODE = '2203.00.00'  
ORDER BY 
    I_COMDTY_ID DESC 
LIMIT 1;