ALU status flags: In a 4-bit ALU, overflow indicators (status flags) assert when addition or subtraction produces a result that does not fit in four bits according to the representation in use. Evaluate this statement.

Introduction / Context:
Status flags (zero, carry/borrow, sign, overflow) summarize arithmetic outcomes. The overflow flag specifically signals that the computed result falls outside the representable range for the chosen width and signedness, which is essential for correct program flow or hardware state transitions.

Given Data / Assumptions:

• ALU width is 4 bits for this discussion.
• Operations considered: addition and subtraction.
• Overflow semantics depend on signed interpretation; carry relates to unsigned arithmetic.

Concept / Approach:
For signed 2's complement, overflow occurs when adding two positives yields a negative, or two negatives yield a positive. In 4 bits, the representable signed range is −8 to +7; results outside this range set overflow. For unsigned, carry-out indicates out-of-range, while a separate overflow definition may be unused; the question's wording focuses on the general idea that results can exceed 4-bit capacity and that indicators exist for this condition.

Step-by-Step Solution:

Verification / Alternative check:
Standard ALUs and CPU ISAs define these flags; 4-bit educational ALUs expose similar indicators for teaching purposes.

Why Other Options Are Wrong:

• Incorrect: Ignores established flag semantics.
• Ambiguous / Cannot be determined: The behavior is well-specified in ALU designs.

Common Pitfalls:
Confusing carry with overflow; carry is an unsigned concept, while overflow is a signed-range violation. Both can inform about out-of-range conditions depending on interpretation.

Final Answer:
Correct