When a scheduled activity cannot be estimated with an adequate degree of certainty, the work within the activity can be decomposed. The resource requirements for each lower, more detailed work package can be estimated and aggregated to form a basis for estimating the overarching scheduled activity. What is this type of estimating called? ❍ A. Bottom-up estimating ❍ B. Decomposed estimating ❍ C. Should-cost estimating ❍ D. Three-point estimating