Which table shows a function whose range has exactly three elements?

Question

x |f(x)
1 | 4
2 | 4
3 | 4

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x |f(x)
3 | 8
4 | 6
5 | 12
6 | 8

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x |f(x)
0 | 5
2 | 9
0 | 15

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x |f(x)
1 | 4
3 | 2
5 | 1
3 | 4

Is the answer D?

Answer 1

Not D, because f(3) has two different values. So, f is not a function.

Answer 2

Is it C? All the f(x) values are different.

Answer 3

It is A