Final answer:
The term 'belvedere' (option 1) describes a building feature designed for viewing pleasant scenes, differing from a rotunda, portico, and cupola which are other architectural elements.
Step-by-step explanation:
The architectural feature designed to offer a view upon a pleasing scene is called a belvedere. This term specifically refers to a structure or architectural feature that allows for panoramic viewing, typically situated on a high point of a building and often fully or partially enclosed by walls and windows.
While a rotunda is a large, circular area with a dome, such as the one found in the Pantheon, and a portico is a covered entrance supported by regular intervals of columns as seen in classical architecture like the Peristyle, and a cupola is a small, dome-like structure that forms part of a roof or ceiling, the belvedere is the one that matches the description of a viewing platform.