To answer this question, let's go through each option to understand the function modules used in Batch Data Communication (BDC):
Option A) BDC_OPEN_GROUP - This function module is used to open a BDC session and initialize the necessary control structures. It is responsible for starting a BDC session and specifying the transaction code for the session.
Option B) BDC_CLOSED_GROUP - This function module is not a valid function module used in BDC.
Option C) BDC_DELETE_GROUP - This function module is not a valid function module used in BDC.
Option D) BDC_INSERT - This function module is used to insert a transaction into a BDC session. It is responsible for populating the necessary data structures with the values to be entered in the screens of the transaction.
The correct answer is A, B, D. These function modules (BDC_OPEN_GROUP, BDC_CLOSED_GROUP, and BDC_INSERT) are commonly used in BDC to open a session, specify the transaction code, and insert transactions into the session, respectively.