At any iteration of the solution algorithm for a minimization problem, the simplex tableau is given below: Basic X X2 S $2 $3 Solution Z 0 0 0 -20 -5 120 S 0 0 1 -4 1 8 X2 0 1 0 3 -1 2 X 1 0 0 2 1 12 Please choose the correct option below. O a. The solution is optimal with Z-value 120 and x1 = 8 and x2 = 12. O b. The solution is not optimal and x2 is the leaving variable. O c. x1, x2 and s3 are the basic variables. Od. The solution is optimal with Z-value 120 and x1 12 and x2 = 2. O e. The solution is not optimal and s2 is the entering variable