Assume that the memory is word addressable. After the execution

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Direction: Consider the following program segments. Here R₁, R₂ and R₃ are purpose registers.

Instruction	Operation	Instruction size (number of words)
MOV R₁, 3000	R₁ ← M [3000]	2
LOOP MOV R₂ , R₃	R₂ ← M [R₃]	1
ADD R₂,	R₂ ← R₁ + R₂	1
MOV R₃ , R₂	M[R₃] ← R₂	1
INC R₃	R₃ ← R₃ + 1	1
DEC R₁	R₁ ← R₁ – 1	1
BNZ LOOP	Branch on not zero	2
HALT	Stop	1

Assume that the content of memory location 3000 is 10 and the content of the register R₃ is 2000. The content of each of the memory locations from 2000 to 2010 is 100. The program is loaded from the memory location 1000. All the numbers are in decimal.

Assume that the memory is word addressable. After the execution of this program, the content of memory location 2010 is

1. 10
2. 11
3. 20
4. 21

Correct Option: D

The memory reference required by the instruction R₁ ← M [3000] is 1 whereas the memory reference required by R₂ ← M[R₃] and M[R₃] ← R₂ is 10. Therefore, total memory reference required = 2 × 10 + 1