The question below comprises four scattered segments of a paragraph. Identify…

Concept: In a para-jumble (sentence re-arrangement) item, the opening sentence must introduce the subject by name -- it cannot open with a pronoun or demonstrative ("he", "this") that has no antecedent yet. Each following sentence should logically extend the idea just stated, and a sentence beginning with a referential word can only appear once its antecedent has already been established in an earlier sentence. The paragraph typically closes with a summarizing or concluding line.

Application: Segment A opens the paragraph because it names "Mr D Gautam" explicitly, establishing the subject that the later pronouns ("he", "his", "this") depend on. Segment C follows A, stating that "he has a fanatical devotion to detail" -- the first concrete elaboration of the personality trait introduced in A. Segment B continues that same elaboration ("Nothing is too small for his attention"), reinforcing the detail-orientation described in C. Segment D closes the paragraph, since "This" in D refers back to the trait built up across C and B, giving the concluding line that this attention to detail "makes him a different guy." The resulting order is A-C-B-D.

Cross-check: Placing D ("This is what makes him a different guy") before B ("Nothing is too small for his attention") would strand B's elaboration after the conclusion has already been drawn, breaking the flow. Opening with C or with D instead of A fails outright, since both C's "He" and D's "This" have no antecedent until the subject has been named -- only A can open the paragraph.