Which statement about inventory (stock) days is correct?

(which one)

a. "stock days" refers to the average time it takes to sell inventory (stock) or products

b. "stock days" refers to the average time it takes to sell inventory (stock) and collect cash from those sales

c. the more quickly a business converts its inventory (stock into sales, the more supporting financing it needs.

d. "stock days" refers to the average time it takes to collect cash from the sale of inventory (stock) items