Which of the following do not represent memory-reference instructions? A. mode…

Concept

Two distinct standards apply here: architectural classification and official examination scoring. In Mano’s basic-computer model, opcodes 000 through 110 are memory-reference operations; opcode 111 with I = 0 is register-reference, and opcode 111 with I = 1 is input-output reference.

For a previous-year examination item, the final answer key issued by the examining authority determines the accepted scored response. When that key conflicts with the textbook classification, the discrepancy must be stated rather than hidden.

Application

1. The archived question paper identifies this stem as Question ID 3767491611 and associates the answer value B & D only with that item.

2. The matching NTA UGC-NET December 2024 final answer key records B & D only as the accepted scored response for Question ID 3767491611.

3. Therefore, the officially accepted response for this PYQ is B & D only.

4. A direct Mano-model check instead classifies B and C as non-memory-reference and classifies A, D, and E as memory-reference, exposing a genuine discrepancy in the official item.

Cross-check

The question paper and the final key use the same question ID, so the result is not caused by reordered choices. The difference is between the authority’s recorded scoring key and the standard architectural derivation.

Result

For this UGC-NET PYQ, the accepted answer is B & D only. Under the standard Mano basic-computer classification, B & C only would be conceptually expected; that conflict is noted explicitly.