Final answer:
To create a vertical box list in a document using SmartArt, the 'Vertical List' SmartArt graphic option is the most suitable choice.
Step-by-step explanation:
When a student is looking to insert a SmartArt graphic in a document to create a vertical box list, the most appropriate option to choose would be 'Vertical List'. This type of SmartArt graphic is designed to show grouped information or sequential steps in a process that are to be viewed from top to bottom, aligning with the description of a vertical layout. It's different from a process diagram, which could be either horizontal or vertical but is generally used for showing steps in a process rather than a simple list. A hierarchical diagram, on the other hand, would be used to show layered relationships, such as a company's organizational chart or a family tree. Therefore, option a) Vertical List is the correct choice for representing a vertical box list in the document.