Password fields often use ____ to conceal data.

Which of the following is NOT true about saving presentations in multiple formats?

A) Using the Share tab on the File tab, you can share your presentation files in a variety of ways, depending on whether or not your presentation file is saved locally, on a SharePoint site, or on SkyDrive. B) Using the Join People option, you can invite people to view or collaborate with you on your presentation, generate a link to share with others, and give them view or edit permissions. C) Using the E-mail option, you can send a presentation via an e-mail as either a PowerPoint, PDF, or XPS attachment, or as a link. D) You can post your presentation to various social networks like Facebook, Twitter, and LinkedIn.

Which of the following are the correct preprocessor commands necessary to prevent multiple inclusions of header files? If there is an answer here that works to prevent multiple inclusion, carefully describe how it works in the explanation.

a)``` #include “header.h” ``` b)``` #define HEADER_H #ifndef HEADER_H //declarations for header.h go here #endif c) `````` #ifndef HEADER_H #define HEADER_H // declarations for header.h go here #endif ``` d)``` #ifndef HEADER_H //declarations for header.h go here #endif ```