Oxygen CAT 2025 Slot 3 Odd Man Out | Hard
Five jumbled sentences (labelled 1, 2, 3, 4, and 5), related to a topic, are given below. Four of them can be put together to form a coherent paragraph. Identify the odd sentence out and key in the number of that sentence as your answer.
1. About half of all the oxygen we breathe is made near the surface of the ocean by phytoplankton that photosynthesize just like land-dwelling plants.
2. A team of scientists that includes Boston University experts has discovered they also produce oxygen on the seafloor.
3. The research team used deep-sea chambers that land on the seafloor and enclose the seawater, sediment, polymetallic nodules, and living organisms.
4. The discovery is a surprise considering oxygen is typically created by plants and organisms with help from the sun—not by rocks on the ocean floor.
5. The deep-sea rocks, called polymetallic nodules, don’t only host a surprising number of sea critters.
Answer & Explanation
Correct Option: 3
Rationale: The coherent paragraph focuses on the discovery that polymetallic nodules on the seafloor produce oxygen, an unexpected finding since oxygen is typically generated through photosynthesis involving sunlight. Sentences describing the nodules, the discovery, why it is surprising, and the general process of oxygen production in the ocean form a complete narrative. Sentence 3, which details the specific research method (deep-sea chambers), disrupts the flow by shifting from the conceptual discovery to procedural details, whereas the other sentences together build the main idea without requiring the methodological explanation.
Why other options are wrong: The remaining sentences (1, 2, 4, 5) all contribute directly to introducing the topic, presenting the discovery, and explaining its significance. Sentence 1 sets up a contrast between normal oxygen production and the surprising new finding, which is essential context.
Difficulty: Hard
Alternately even Option: 1 can be Correct.
Rationale: The coherent paragraph focuses on the discovery of oxygen production by deep-sea polymetallic nodules. Sentences describing the nodules, the discovery, its surprising nature, and the methodology form a complete narrative. Sentence 1, which discusses surface phytoplankton, is tangential to this discovery.
Why Option 1 is not the answer in CAT key: Sentence 1 provides essential contrast — it establishes the conventional understanding (oxygen from surface phytoplankton) against which the surprising deep-sea discovery is highlighted. Removing it weakens the “surprise” factor emphasized in sentence 4. Therefore, sentence 1 belongs to the conceptual paragraph, while sentence 3 is an explanatory aside about methodology.
Why 5 can be answer: Some experts might argue that if there were an option 5 explicitly describing strict deontology (rules regardless of outcomes, with no mention of maximizing benefit), it would be the true philosophical opposite of utilitarianism.
Why CAT key rejected 5 as answer: There is no option 5 in the given question — only options 1 to 4. Even if it existed, the question might define “opposite” in practical policy terms, not just pure ethical theory, making prioritarianism (option 1) the safer exam choice.
Difficulty: Hard
Music CAT 2025 Slot 3 Odd Man Out | Moderate
Five jumbled sentences (labelled 1, 2, 3, 4, and 5), related to a topic, are given below. Four of them can be put together to form a coherent paragraph. Identify the odd sentence out and key in the number of that sentence as your answer. Moderate
1. The profound emotional impact of music has inspired ongoing research into its relationship with emotions.
2. Music is a universal phenomenon that utilizes a myriad brain resources.
3. This inherent connection to musical expression is deeply intertwined with human identity and experience.
4. The proclivity to create and appreciate music is ubiquitous among humans, permeating daily life across diverse societies.
5. Engaging with music is among the most cognitively demanding tasks a human can undergo, and it is identified across cultures.
Answer & Explanation
Correct Option: 1
Rationale: The paragraph focuses on music’s universality, ubiquity, connection to identity, and cognitive demand. Sentence 1 shifts attention to research about music rather than music’s inherent qualities, breaking thematic coherence.
Why other options wrong: Sentences 2, 3, 4, and 5 consistently describe intrinsic features of music and fit together as a coherent whole.
Difficulty: Medium
