Final answer:
Manufacturers must give both cash and machine hours to get inventory, which are factors of production necessary in acquiring materials and utilizing machinery for production.
Step-by-step explanation:
In order for a manufacturer to get inventory, they must give various resources that are used to produce goods and services, known as factors of production. The correct answer to the student's question would be: E. A and C - Cash and Machine Hours. This is because both cash and machine hours are resources that manufacturers utilize to obtain inventory. Cash is used to purchase raw materials, pay wages, and acquire other necessary items, while machine hours represent the use of machinery, which is another key factor in the production process. Therefore, both are essential for a manufacturer to create inventory that can later be sold in the market for goods and services (product market).