Given:
The graph of set of ordered pairs.
To find:
The domain of the set of number.
Solution:
Domain is the set of input values or x-values.
From the given graph it is clear that the set of ordered pair is:
{(1,2), (2,4), (3,1), (4,6), (5,4), (6,5)}
Here, the x-values are 1, 2, 3, 4, 5, 6. So, the domain is the set of these values.
Domain = {1, 2, 3, 4, 5, 6}
Therefore, the correct option is A.