A sentence-processing machine transforms a string of words in a fixed pattern. Example: Input: Honesty is the best policy Step 1: is Honesty the best policy Step 2: is the Honesty best policy Step 3: is the best Honesty policy Step 4: is the best policy Honesty Output after 4 steps: is the best policy Honesty Now, if the input is: A rolling stone gathers no moss what will be the fifth word in the string after 4 steps of the same process?

Introduction / Context:
This logical reasoning question deals with pattern recognition in word rearrangement. A machine repeatedly transforms a sentence according to a consistent rule. Your task is not only to trace the pattern from the example, but also to apply it to a new input and identify the word that occupies a specific position after several steps.

Given Data / Assumptions:

• Example input: “Honesty is the best policy”.

• After each step, the words are rearranged in a particular pattern, producing four steps in the example.

• New input: “A rolling stone gathers no moss”. This has six words: A, rolling, stone, gathers, no, moss.

• We must find the fifth word after performing 4 steps of exactly the same transformation rule.

Concept / Approach:
We must first infer the transformation rule from the example. Then we consistently apply this rule step-by-step to the new sentence. The key is to see how, at each step, one specific word swaps its position with its neighbour, gradually moving words toward the front of the sentence.

Step-by-Step Solution:
Step 1 (understanding the rule from the example): Input: Honesty is the best policy. Step 1: is Honesty the best policy — here, the word at position 2 (“is”) swaps with the word at position 1 (“Honesty”). Step 2: is the Honesty best policy — starting from Step 1, the word at position 3 (“the”) swaps with the word at position 2 (“Honesty”). Step 3: is the best Honesty policy — now, the word at position 4 (“best”) swaps with the word at position 3 (“Honesty”). Step 4: is the best policy Honesty — finally, the word at position 5 (“policy”) swaps with the word at position 4 (“Honesty”). This shows the pattern: at step k, the word originally at position k+1 is swapped left by one place with the word at position k. Step 2 (apply the rule to the new sentence “A rolling stone gathers no moss”): Initial (Step 0): A rolling stone gathers no moss. Step 1 (swap positions 1 and 2): rolling A stone gathers no moss. Step 2 (swap positions 2 and 3): rolling stone A gathers no moss. Step 3 (swap positions 3 and 4): rolling stone gathers A no moss. Step 4 (swap positions 4 and 5): rolling stone gathers no A moss. Step 3 (identify the fifth word after 4 steps): In Step 4, the sentence is “rolling stone gathers no A moss”. The fifth word is “A”.

Verification / Alternative check:
You can verify by explicitly writing each step in a column, marking positions from 1 to 6 each time. You will observe that after 4 steps, the sequence of words is exactly “rolling stone gathers no A moss”. The fifth position clearly holds the word “A”.

Why Other Options Are Wrong:
Option A (“Moss”) is wrong because “moss” remains at the sixth position throughout the four steps in this pattern.
Option B (“No”) is wrong because “no” ends up in the fourth position, not the fifth, after Step 4.
Option C (“Stone”) is wrong because “stone” settles in the second position by the time we reach Step 4.

Common Pitfalls:
A typical mistake is to guess that the pattern simply rotates words or moves the last word to the end without carefully checking each given step. Another error is to miscount the positions of words after each swap. To avoid confusion, always label positions 1, 2, 3, and so on at every step, and apply the same transformation rule consistently.

Final Answer:
Therefore, the fifth word in the string after four steps of processing is A.