Which of the following statement is correct with regard to job costing?

• A. Job costing differs from most other types of costing system because each cost unit is a job, and no two jobs are exactly the same. Each job is costed separately.
• B. The expected cost of a job has to be estimated so that a price for the job can be quoted to a customer.
• C. A costing system should also calculate the actual cost of each job that has been carried out to work out the relative profitability of relevant jobs.
• D. All of the above are correct