An architecture enthusiast based in New York City develops an application that enables a user to point her phone camera at any building in Manhattan, and then see an overlay on her phone that includes not only a picture of the building, but also a list of architectural details, including the year it was built, its design style, and its dimensions. Such app is an example of:

a$.$

Virtual Reality $($VR$).$

b$.$

Augmented Reality $($AR$).$

c$.$

ColdFusion server software.

d$.$

$3-$D Printing.