Answer: For a relation to be a function, each x-value must map to only one y-value. In this case, when x = 5, it maps to both y = 8 and y = 5. Since one x maps to two different y-values, the relation B is not a function. So, no value of x will make it a function as long as (5, 8) and (x, 5) coexist in the relation.