According to Microsoft, ODBC is a specification for a database API. This API is database and operating system agnostic due to the fact that the primary goal of the ODBC API is to be language-independent. Additionally, the open functions of the API are created by the manufactures of DBMS-specific drivers. Developers can use these exposed functions from within their own custom applications so that they can communicate with DBMS through the language-independent drivers.
ODBC Transaction Isolation Levels are related to and limited by the transaction management capabilities of the data source.
Transaction isolation levels: