Question

Function problem

Answer 1

Nope, in a function, there's a UNIQUE value in the range for every value in the DOMAIN,
in option D you have 2 values for 7, which are 5 and 3, this is not unique so it's not a function, but it's a relation

Answer 2

Yep, on the other hand if you look at B, it's not a function since you have 2 distinct values for -6, so it's just a relation and option C is not even a relation, it's just a set