Question 1

Which one of the following is the odd one out?
January, March, May, June

Accepted Answer

January, March, and May are all months with 31 days. June is a month with only 30 days.

Question 2

Which one of the following is the odd one out?
Pencil, Pen, Eraser, Sharpener

Accepted Answer

Pencil, Pen, and Sharpener are all writing/maintenance instruments used with pencils. Eraser is used to remove marks made by pencil, but it is not a writing instrument itself—it serves a corrective purpose rather than a writing purpose.

Question 3

Which one of the following is the odd one out?
Sparrow, Peacock, Penguin, Eagle

Accepted Answer

Sparrow, Peacock, and Eagle are all birds that can fly. Penguin is a bird that cannot fly—it is flightless and adapted for swimming instead.

Question 4

Which one of the following is the odd one out?
Rose, Lily, Cactus, Tulip

Accepted Answer

Rose, Lily, and Tulip are all flowering plants that require regular watering and grow in temperate climates. Cactus is a succulent plant adapted to arid/desert climates and requires minimal water.

Question 5

Which one of the following is the odd one out?
Swimming, Running, Cycling, Sleeping

Accepted Answer

Swimming, Running, and Cycling are all physical activities/sports that require active movement and exercise. Sleeping is a rest activity that is the opposite of physical exertion.

Question 6

Find the odd one out: Pen, Pencil, Eraser, Sharpener

Accepted Answer

Pen is the odd one out because it is a writing instrument that produces permanent marks, whereas Pencil, Eraser, and Sharpener are all tools used to modify or maintain pencils. Pencil makes marks that can be erased, Eraser removes pencil marks, and Sharpener maintains the pencil's point.

Question 7

Find the odd one out: Sparrow, Penguin, Ostrich, Kiwi

Accepted Answer

Sparrow is the odd one out because it is a flying bird, whereas Penguin, Ostrich, and Kiwi are all flightless birds. These three have evolved to lose the ability to fly and have adapted to terrestrial or aquatic environments instead.

Question 8

Find the odd one out: Violin, Guitar, Piano, Flute

Accepted Answer

Flute is the odd one out because it is a wind instrument (produces sound by air vibration), whereas Violin, Guitar, and Piano are all string instruments (produce sound by vibrating strings). Flute requires blowing air, while the other three require plucking or striking strings.

Question 9

In a classification task, which one of the following does NOT belong to the same group as the others?

A) Emerald
B) Sapphire
C) Diamond
D) Graphite

Accepted Answer

Emerald, Sapphire, and Diamond are all precious gemstones valued for jewellery and rarity. Graphite, while crystalline like diamond, is not a precious gemstone—it is an industrial mineral used in pencils, lubricants, and manufacturing. The classification principle is 'precious gemstones used in jewellery,' which graphite does not satisfy.

Question 10

Which one of the following does NOT belong to the same logical group?

A) Ostrich
B) Penguin
C) Kiwi
D) Sparrow

Accepted Answer

Ostrich, Penguin, and Kiwi are all flightless birds—they possess wings but cannot fly. Sparrow is a fully capable flying bird. The classification principle is 'flightless birds,' which sparrow does not satisfy.

Question 11

Which one of the following does NOT belong to the same logical category?

A) Metaphor
B) Simile
C) Irony
D) Alliteration

Accepted Answer

Metaphor, Simile, and Irony are all figures of speech that involve semantic meaning or conceptual comparison—they convey ideas through non-literal language or unexpected meaning. Alliteration is a phonetic/sound device based on repetition of initial consonant sounds, not on semantic or conceptual meaning. The classification principle is 'figures of speech involving semantic/conceptual meaning,' which alliteration does not satisfy.

Question 12

Which one of the following does NOT belong to the same group?

A) Mitochondrion
B) Chloroplast
C) Ribosome
D) Lysosome

Accepted Answer

Mitochondrion, Chloroplast, and Lysosome are all membrane-bound organelles (they possess a lipid bilayer boundary). Ribosome is a non-membrane-bound organelle—it consists only of RNA and protein without any surrounding lipid membrane. The classification principle is 'membrane-bound organelles,' which ribosome does not satisfy.

Question 13

Which one of the following does NOT belong to the same logical category?

A) Monarchy
B) Oligarchy
C) Democracy
D) Anarchy

Accepted Answer

Monarchy, Oligarchy, and Democracy are all established systems of government with defined structures, authority hierarchies, and rule of law. Anarchy is the absence of government—it is not a system of government but rather the negation of governmental structure. The classification principle is 'systems of government with formal authority structures,' which anarchy does not satisfy.

SSC MTS Classification / Odd One Out

Classification / Odd One Out— Rules & Concept

Key Points to Remember

Exam-Specific Tips

Classification / Odd One Out — Practice Questions

60-Second Revision — Classification / Odd One Out