Which of the following relations is a function?

a. { (-1, 4), (1,3), (2, 3), (3, 1) }

b. { (2,3), (4, 8), (1,3), (2, 4) }

c. { (2, 3), (3, 1), (2, 1), (3, 2) }

d. { (1, 1), (1, 2), (1, 3), (1, 4) }

I think its a

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Solve this Question 134x23/5^3

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