Question

Let A = {a, b, c, d}. Which of the following relations is a function from A to A? *
{(a, b), (b, d), (c, a), (d, b)}
{(a, a), (a, b), (b, c), (b, d)}
{(a, b), (b, c), (c, d)}
{(a, b), (a, c), (b, a)}​

Answer 1

Answer:

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