Answer the Following Questions Using the Information Below

Answer the following questions using the information below:
Tri-State Manufacturing expects to spend $800,000 in 2012 in appraisal costs if it does not change its incoming materials inspection method. If it decides to implement a new receiving method, it will save $80,000 in fixed appraisal costs and variable costs of $0.40 per unit of finished product. The new method involves $120,000 in training costs and an additional $160,000 in annual equipment rental. It takes two units of material for each finished product.
Internal failure costs average $160 per failed unit of finished goods. During 2011, 5% of all completed items had to be reworked. External failure costs average $400 per failed unit. The company's average external failures are 1% of units sold. The company carries no ending inventories, because all jobs are on a per order basis and a just-in-time inventory ordering method is used.
-Companies that use manufacturing lead time as the base for allocating manufacturing costs to products consider that it has the following benefit(s) :

A) Managers are motivated to reduce the time taken to manufacture products.
B) Total overhead costs decrease.
C) Operating income rises.
D) All of these answers are correct.