Three friends A, B, and C decide to run around a circular track. They

If you go by the answers choices , then both C and E satisfies the condition. According to each answer choice, take A's speed as the number of equally spaced points on the circle and then check the positioning of B and C as asked in the question. You will get both choice C and E as answers.
Obviously the question is wrong.

Let say Circular Lap was x km

B was a km behind A when A completed lap

so Position of B = x - a km

position of C = x -a - a = x - 2a km

let say t was time taken

Speed of A , B & C respectively = x/t , (x-a)/t , (x-2a)/t

When A completed 3 laps distance covered by a = 3x

time take = 3x/(x/t) = 3t

B completed the distance = 3x - 3a km

C completed the Distance = 3x - 6a km

3x - 6a has same position as x-a

either 3x - 6a = x-a (did not complete even single lap)

or 3x-6a = x + x - a (completed one lap)

=> x = 5a/2 or x = 5a

Ratio of Speed of A, B , C are (5a/2)/t : (5a/2 - a)/t : (5a/2 - 2a)/t ,

5 : 3 : 1

or

Ratio of Speed of A, B , C are (5a)/t : (5a - a)/t : (5a - 2a)/t ,

5 : 4 : 3

5 : 4 : 3 is the option given so this is the right answer

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