Which of the following is not a control structure?

When using Facebook for professional networking and posting status updates, it makes sense to practice ________

A) writing posts like you write text messages to friends B) discretion C) marketing what you have to offer D) mixing your personal and professional lives

In C:\Users\Sue\Documents\spreadsheets\fall17.xlsx, .xlsx is an example of a file name ________

Fill in the blank(s) with correct word