Which statement is true about Bottom-up estimating?

A.
Estimating the cost of individual work items and then rolling up the costs to arrive at a project total.

B.
Uses the actual cost of a previous similar project as the basis for estimating the cost of the current project.

C.
Using project characteristics (or parameters) in a mathematical model to predict costs.

D.
Cost of quality can also be used to prepare the schedule activity cost estimate.

Explanation:
Bottom-up estimating: Estimating the cost of individual work items and then rolling up the costs to arrive at a project total. It is more accurate.