Answer:
Step-by-step explanation:
We are given four sets of relations as
![A. {(-1, 1) (0, 0) (1, 1) (2, 4)} \\B. {(3, 4) (2, 3) (3, 6) (2, 0)} \\C. {(1, 0) (2, 3) (3, -2) (1, 6)} \\D. {(3, 2) (3, -2) (3, 6) (3, 8)}](https://tex.z-dn.net/?f=A.%20%7B%28-1%2C%201%29%20%280%2C%200%29%20%281%2C%201%29%20%282%2C%204%29%7D%20%5C%5CB.%20%7B%283%2C%204%29%20%282%2C%203%29%20%283%2C%206%29%20%282%2C%200%29%7D%20%5C%5CC.%20%7B%281%2C%200%29%20%282%2C%203%29%20%283%2C%20-2%29%20%281%2C%206%29%7D%20%5C%5CD.%20%7B%283%2C%202%29%20%283%2C%20-2%29%20%283%2C%206%29%20%283%2C%208%29%7D)
A function is a relation in which every element in the first set has a unique image in the second set.
Let us check this aspect to A.
This is a function
Now come to B. 3 has two images 4 and 6. so not a function
Next is C. in C 1 has two images 0 and 6. So not a function
For D, 3 has 4 images so not a function.