The correct answer is: B. historical
Cost accounting is a branch of accounting that tracks and analyzes costs. It is used to determine the cost of goods sold, the cost of services, and the cost of production. Cost accounting is based on historical data, which is data that has already been collected. This data can be used to estimate future costs, but it is important to remember that historical data is not always accurate.
Option A: Estimated figures are not always accurate, as they are based on assumptions about future events.
Option C: Actual figures are the most accurate, but they can be difficult to collect.
Option D: None of these is the correct answer, as cost accounting is based on historical data.