Final answer:
The legend of a Gantt Chart can include the project start date, company name, and project duration; hence, 'all of the above' is the correct answer.
Step-by-step explanation:
In the legend section of a Gantt Chart, you can add a variety of information to provide clear context about the project being represented. Specifically, you can include the project start date, which provides a reference for when the project timeline commences; the company name, offering a clear identification of who is responsible for or who owns the project; and the project duration, which outlines the total time span planned for the project to be completed. Therefore, the answer to your question is that in the legend section of a Gantt Chart, you can add all of the above information.