Answer:
(A) will have a dual price of zero.
Step-by-step explanation:
A slack variable is a variable that is added to an inequality constraint to transform it into an equality. if a slack variable is positive at a particular candidate solution, the constraint is non-binding there, as the constraint does not restrict the possible changes from that point. If a slack variable is negative at some point, the point is infeasible (not allowed), as it does not satisfy the constraint.
Also, if a slack variable value is positive, its dual price is zero. If a slack variable value is zero, its dual price is positive.