Aviation and Airport Security Practice Test.

The database designed for easy use and acting as a single point of inquiry for travel-related issues of airline passengers is called PIA. This option is the best choice because the other options are not related to travel or databases. TSA stands for Transportation Security Administration and is responsible for security at airports, not database management. FAA stands for Federal Aviation Administration and is responsible for regulating civil aviation and promoting safety, not database management. NADA is not a known acronym in the context of travel or databases and therefore is not a viable option. PIA stands for Passenger Inquiry Application and is specifically designed to be user-friendly and address travel-related issues for airline passengers, making it the most suitable choice for the given question.