I'd go with command-line interface.
A CLI enables users to type commands in a console or a terminal window expressed as a sequence of characters and presses the enter key on the keyboard to execute that command. And in this case, Sarah is typing an “open document 3” command to the command-line interface to open a file in her computer.
Answer:
B. n-1
Explanation:
If there are n vertices then that vertex can be origin of at most n-1 edges.Suppose that you have a graph with 8 vertices you can select a vertex from these 8 vertices now you have 7 other vertices.So the vertex you selected can have at most 7 edges or it can be origin of at most 7 edges.So we conclude that the answer is n-1.
C. a payday lender is a type of loan