Answer:
A. B and C are functions
Explanation:
Given
See attachment for mapping diagrams
Required
Which represent function
For a mapping to be considered a function, each element of the input set must only point to 1 element of the output set.
Base on the above analysis, we have:
Map A
1 points to 6; 2 to 7; 3 to 8; and 4 to 9
This is a function
Map B
2 points to 0; 4 to 0; 6 to 0; and 8 to 0
This is a function
Map C
1 points to 8; 3 to 8; 5 to 9; and 7 to 9
This is a function
Map D
0 points to 2 and 5; 3 points 7 and 9
This is not a function