CAT 2025

Slot 2

VARC

Question & SolutionQues & Sol

The four sentences (labelled 1, 2, 3, and 4) given below, when properly sequenced, would yield a coherent paragraph. Decide on the proper sequencing of the order of the sentences and key in the sequence of the four numbers as your answer.

1. As books age, the cellulose and lignin in the paper begin to break down, releasing a mix of volatile organic compounds into the air.
2. Old books carry a scent that many people instantly recognize—and even love.
3. These compounds are benzaldehyde, which gives off an almond-like scent, vanillin, which smells like vanilla, ethyl hexanol (floral scent), toluene (sweet), and furfural (which has a slightly bready scent).
4. This familiar aroma isn't just dust or mildew; it's actually a result of slow chemical changes happening inside the paper and ink.

1. Key Idea & Flow

This paragraph is fundamentally about why old books smell the way they do — moving from the general human experience of that scent, to the chemical explanation behind it, and finally to the specific compounds responsible. The key structural logic is: introduce the phenomenon -> explain it broadly -> explain it chemically -> enumerate the specific chemicals.

The critical anchor here is Sentence 4, which uses the phrase 'this familiar aroma' — a demonstrative reference that can ONLY point back to a prior sentence that introduced 'a scent.' This locks Sentence 2 before Sentence 4. Similarly, Sentence 3 opens with 'These compounds,' which must refer back to Sentence 1's mention of 'a mix of volatile organic compounds.' This locks Sentence 1 before Sentence 3.

2. Building the Sequence Step by Step

Step 1 — Find the Opening Sentence: Sentence 2 — 'Old books carry a scent that many people instantly recognize — and even love' — is the most general, topic-introducing statement. It requires no prior context, names no chemicals, and sets up the 'what' before the 'why.' This is clearly the opener.

Step 2 — Find What Follows Sentence 2: Sentence 4 says 'This familiar aroma isn't just dust or mildew; it's actually a result of slow chemical changes happening inside the paper and ink.' The phrase 'this familiar aroma' directly references the scent introduced in Sentence 2. Sentence 4 acts as the first layer of explanation — reframing the scent as a product of chemistry, not mere age or dirt. Order so far: 2 -> 4

Step 3 — Find What Follows Sentence 4: Sentence 1 says 'As books age, the cellulose and lignin in the paper begin to break down, releasing a mix of volatile organic compounds into the air.' This sentence deepens the chemical explanation introduced in Sentence 4's 'slow chemical changes' — it names the specific molecules (cellulose, lignin) and the process (breaking down into volatile organic compounds). It is the mechanistic elaboration of Sentence 4's broad claim. Order so far: 2 -> 4 -> 1

Step 4 — Find the Closing Sentence: Sentence 3 says 'These compounds are benzaldehyde, which gives off an almond-like scent, vanillin, which smells like vanilla, ethyl hexanol (floral scent), toluene (sweet), and furfural (which has a slightly bready scent).' The phrase 'these compounds' is an unmistakable back-reference to the 'volatile organic compounds' named in Sentence 1. Sentence 3 is the most specific and list-like, making it a natural paragraph-ender. Final Order: 2 -> 4 -> 1 -> 3

3. The Logical Chain Visualized

Answer = 2413 ✅

Always begin by identifying the most general, context-free sentence as the opener, then trace the chain of demonstrative references ('this,' 'these') and pronoun anchors to lock the remaining sentences into place.