Hannah Jackson is a project manager at an e$-$Learning organization. Her team has to develop an e$-$Learning course of three learning hours within two months. To begin estimating the resources required for completing the project, she refers to a document that contains a list of all the project tasks needed to complete this project.

To which document is Hannah referring?

A$)$ activity list

B$)$ resource breakdown structure

C$)$ organizational breakdown structure

D$)$ milestone schedule