Hi @Keshavi Patel ,
As per the discussion with internal team, AD uses 3rd party Informix driver to source data. It should support all data types supported by Informix available with sdk.
Best option is to query table with clob/blob column and see if that source table columns are copied to sink.
You can try to source CLOB by using CAST(column AS VARCHAR(n)), it is also possible to source BLOB (Informix BYTE data type) using ODBC linked service.
Hope this info helps. Do let us know if you have further questions.