You can verify the answer using numerical examples.
However, please note that what is given is a mathematical axiom
For a given circumference or perimeter, an equilateral triangle will be the regular polygon with the smallest area and a circle will the figure with the largest area.
A square with 4 sides having the same perimeter as that of an equilateral triangle will have an area larger than the equilateral triangle. Similarly, a regular pentagon's area will be larger than that of a square for the same perimeter and so on and so forth.
The answer to the question is option (3). i.e., C > S > T
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2IIM - IIM CAT Classes, Study Material
Weekend Batch for CAT 2012 starts Sep 18, 2010 @ Mylapore, Chennai.Quant and DI Core Faculty : IIM Graduates. Batch size < 20 students.