In design (architectural, landscape, urban, graphic, etc.), a focal point is an element or area that first attracts the viewer's attention and becomes the center of interest. It is a point of emphasis that draws the eye and can help to organize the composition.
Let's consider the options:
(a) Focal Point (or Point of Focus): This term directly describes a central point of emphasis or interest in a design composition or space. It's the element that stands out and captures attention.
(b) Vista: A vista is a long, narrow view, often framed by rows of trees, buildings, or other elements, typically leading to a terminal feature or focal point at its end. The vista is the view itself, while the object at the end of the vista might be a focal point.
(c) Imageability (as defined by Kevin Lynch): Imageability refers to the quality of a place that makes it recognizable, memorable, and distinct – the ease with which its parts can be recognized and organized into a coherent pattern. Lynch identified elements like paths, edges, districts, nodes, and landmarks that contribute to imageability. While a landmark can be a focal point, "imageability" is a broader concept about the overall legibility and identity of a place.
(d) Visual Survey: A visual survey is a method of collecting information about the visual characteristics of an area or site (e.g., views, landmarks, aesthetic quality, building conditions). It's an analytical tool, not a design element itself.
The term that specifically describes the central point of interest in a design or urban space is Focal Point.
\[ \boxed{\text{Focal Point}} \]