SSC IMD SA 2017 – Question 153

Which of the following must be the last statement of a source program?

• STOP
• RETURN
• OP
• END

Detailed Explanation:

The correct answer is d) End.

In assembly and compiler source programs, statements are divided into executable instructions and assembler directives:

• END Directive: Must be the physically final statement in an assembly source program. It signals to the assembler that there are no further source lines to translate, officially terminating the assembly process. It may also specify the program’s execution entry point label (e.g., END START).
• Why STOP is not the source end statement: STOP (or HLT) is an executable CPU instruction that halts the processor at runtime. A program may have multiple STOP instructions, or none at all (e.g., looping indefinitely or returning to the OS), but it must have exactly one END directive marking the end of the source text.
• RETURN: Used at the end of a subroutine/function to return control to the calling routine.