Odd One Out Question 4 - CAT 2025
Why Odd One Out is Important for CAT
The Odd One Out (Sentence Oddity) question has been one of the recurring Verbal Ability (VARC) question types in CAT. Here is the year-wise trend (all 3 slots combined):
| CAT Year | Odd One Out Questions per Slot | Total Across 3 Slots |
|---|---|---|
| 2025 | 2 | 6 |
| 2024 | 2 | 6 |
| 2023 | 2 | 6 |
| 2022 | 0 (Not asked) | 0 |
| 2021 | 2 | 6 |
| 2020 | 2 | 6 |
| 2019 | 2 | 6 |
| 2018 | 2 | 6 |
| 2017 | 2 | 6 |
Trend Summary
- 2017–2021: Consistently 2 Odd One Out questions per slot.
- 2022: Not asked. It was replaced by Sentence Insertion/Para Completion questions.
- 2023: Reintroduced with 2 questions per slot.
- 2024–2025: Continued with 2 questions per slot.
Total (CAT 2017–2025):
- 48 Odd One Out questions were asked across all slots (excluding 2022).
For CAT aspirants, Odd One Out is a high-return topic because:
- It is a TITA (Type In The Answer) question.
- There is no negative marking.
- It generally tests paragraph coherence and logical flow rather than grammar.
Question
Question 4
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.
- Pfas are a class of about 15,000 compounds most frequently used to make products water-, stain- and grease-resistant.
- New research suggests exposure to some common perfluoroalkyl and polyfluoroalkyl substances (Pfas) cause changes to gene activity and that these changes are linked to health problems including multiple cancers, neurological disorders and autoimmune disease.
- These Pfas compounds are dubbed “forever chemicals” because they do not naturally break down in the environment.
- The research may also point toward other diseases potentially caused by Pfas that have not yet been identified.
- The findings are a major step toward determining the mechanism by which the chemicals cause disease and could help doctors identify, detect and treat health problems for those exposed to Pfas before the issues advance.