There are seven inputs to the estimate activity durations process.

The scope baseline is not an input to the estimate activity durations process. The project's scope statement is an input, but according to the PMBOK, the scope baseline is not. The seven inputs to this process are: activity list, activity attributes, activity resource requirements, resource calendars, project scope statement, enterprise environmental factors, and organizational process assets.

Answer options C, B, and D are incorrect. These all are an input to the estimate activity durations process.