Answer:
Option D. Keeping inventory levels low
Explanation:
The reason is that Just in time system was first introduced in the Japan to lower the inventory level to almost zero to gain cost advantage over the rival companies and also to increase the competitiveness of the domestic products because they are now incurring insignificant cost on the inventory management. This system was introduced to lower the warehouse cost and holding cost by keeping the inventory levels so low that it gives cost advantage.