What is the sequence of steps(order of preparation) for the operating budget?

a. sales budget, schedule of cash collection from customers, purchases and cost of goods sold budget, schedule of cash disbursements for purchases, operating expenses budget.

b. sales budget, capital budget, operating expenses budget.

c. sales budget, purchases and cost of goods sold budget, schedule of cash collection from customers , operating expenses budget.

d. sales budget, operating expenses budget, purchases and cost of goods sold budget.