To answer this question, we need to understand the different elements involved in a COBOL IMS program.
Option A) DLITCBL - This option is incorrect. "DLITCBL" is not a valid COBOL IMS program statement.
Option B) CBLTDLI - This option is incorrect. "CBLTDLI" is not a valid COBOL IMS program statement.
Option C) GOBACK - This option is incorrect. "GOBACK" is a COBOL statement used to terminate a program, but it is not specific to IMS programs.
Option D) PCB mask - This option is incorrect. "PCB mask" refers to the Program Control Block (PCB) mask used in IMS programs, but it is not the first statement in a COBOL IMS program.
Option E) DBD - This option is incorrect. "DBD" refers to the Database Descriptor (DBD) used in IMS programs, but it is not the first statement in a COBOL IMS program.
The correct answer is A) DLITCBL. This option is correct because "DLITCBL" is the first statement in a COBOL IMS program. It is used to initiate the IMS environment and establish communication between the COBOL program and the IMS database.