Answer: B. 1023, 1500, 2000}
Step-by-step explanation:
The Optimal solution should contain the set of quantities that would require the lowest no. of orders to achieve a discount in a class.
1,023 is quite close to the lowest amount required of 1,000 in the 1,000 to 1,499 range.
So are 1,500 and 2,000.
Option D can also work but it has too many order quantities and will inflate the price.
The Optimal Solution therefore has to be from this option.