Select the correct answer.
Which example sets a constraint to validate user input?

1. web and mobile applications allow users to be actively engaged in an online activity. a true b false 2. some examples of business applications purposes are to collaborate, share files, meet virtually in real-time, and accept payments. a true b false 3. an education application would most likely do which of the following? a allow users to watch popular movies and tv shows b connect users with social and business contacts c confirm users' travel plans d teach users a new language 4. a uniform resource locator (url) is how the internet knows where to take users when an address is typed into a browser. a true b false 5. deon is required to provide the citation information for his sources. what type of information should he collect from his sources? a author name, title, date of publication, date of access, url b connections to background information c interesting facts and statistics d notes on important information