In a standard COBOL program, which divisions, sections, and paragraphs are mandatory, and which ones are optional for a minimal but valid program structure?

Introduction / Context:
COBOL organizes source code into a hierarchical structure of divisions, sections, and paragraphs. This structure gives the compiler information about program identity, environment, data, and logic. While many programs will use all four standard divisions, a minimal COBOL program can omit some divisions and sections as long as certain key elements remain. This question asks which divisions and paragraphs are truly mandatory for a valid COBOL program.

Given Data / Assumptions:

• The COBOL standard defines four main divisions: IDENTIFICATION, ENVIRONMENT, DATA, and PROCEDURE.
• Some divisions and sections are optional and may be omitted in simple programs.
• The program must still provide enough information for the compiler to know the program name and executable logic.
• The question focuses on the minimum required structure, not best practices for large systems.

Concept / Approach:
The IDENTIFICATION DIVISION is required in COBOL, and within it the PROGRAM-ID paragraph is mandatory because it provides the program name. The PROCEDURE DIVISION is also required because it contains the executable statements of the program. ENVIRONMENT DIVISION and DATA DIVISION are often present in real world applications but are technically optional if the program does not use external files or declared data. Likewise, many sections and paragraphs within these divisions are optional. A minimal program might have only IDENTIFICATION DIVISION with PROGRAM-ID and PROCEDURE DIVISION with a single paragraph and simple logic.

Step-by-Step Solution:
Step 1: Identify IDENTIFICATION DIVISION as mandatory and PROGRAM-ID as the required paragraph within it to name the program. Step 2: Recognize PROCEDURE DIVISION as mandatory because it holds the logic that will execute when the program runs. Step 3: Note that ENVIRONMENT DIVISION and DATA DIVISION are not strictly required for programs that do not use external files or data items beyond literals. Step 4: Conclude that the minimal structure consists of IDENTIFICATION DIVISION with PROGRAM-ID and PROCEDURE DIVISION with at least one paragraph or section.

Verification / Alternative check:
COBOL language references give examples of very simple programs that contain only IDENTIFICATION DIVISION, PROGRAM-ID, and PROCEDURE DIVISION with basic DISPLAY and STOP RUN statements. These examples compile successfully, confirming that a program can be valid without ENVIRONMENT and DATA divisions. They also emphasize that PROGRAM-ID is required in the IDENTIFICATION DIVISION, which supports the statement in the correct option.

Why Other Options Are Wrong:
Option B is wrong because it claims every division, section, and paragraph is mandatory, which contradicts minimal program examples in documentation. Option C incorrectly states that IDENTIFICATION DIVISION can be skipped, which is not allowed by the language standard. Option D mislabels DATA DIVISION as the only mandatory division, which is incorrect since procedure logic must exist. Option E suggests that the compiler infers structure from comments alone, which is not true for COBOL.

Common Pitfalls:
A common pitfall is assuming that ENVIRONMENT and DATA divisions are always required, which leads to unnecessary boilerplate in very small programs. Another issue is misplacing PROCEDURE DIVISION logic or forgetting the PROGRAM-ID paragraph, causing compilation errors. While professional programs will typically use all divisions and appropriate sections, understanding the minimal requirements helps when creating small test programs or teaching the language. It also clarifies which parts of the structure are essential to program identity and execution.

Final Answer:
At minimum, a COBOL program must have an IDENTIFICATION DIVISION with a PROGRAM-ID paragraph and a PROCEDURE DIVISION; other divisions and sections such as ENVIRONMENT DIVISION and DATA DIVISION are optional depending on the program