The question asks for a term associated with the "overall visual experience and impressions gathered while observing and analysing a space." This suggests a process of observation and assessment.
Let's define the options:
(a) Imageability (Kevin Lynch): This refers to the quality of a physical environment (like a city or space) that evokes a strong, vivid image in an observer. It's about how easily the parts of a place can be recognized, organized into a coherent pattern, and remembered. It's a quality *of the place*, not the act of observing itself, though observation leads to forming an image.
(b) Visual Survey (or Visual Assessment / Visual Analysis): A visual survey is a systematic process of observing, analyzing, and documenting the visual characteristics of a place or environment. This includes identifying key visual elements, views, vistas, landmarks, spatial qualities, aesthetic character, visual sequences, and overall visual impressions. The "overall visual experience and impressions gathered" are precisely what a visual survey aims to capture and understand.
(c) Wayfinding: This is the cognitive and behavioral process by which people orient themselves and navigate through space. While visual cues are critical for wayfinding, "wayfinding" is the act of navigation, not the general visual experience or analysis of a space.
(d) Focal Point: A focal point is a specific element or area in a design or space that attracts the viewer's attention first and serves as a center of interest. It's one component of the visual experience, not the overall experience or the process of gathering impressions.
The term that best describes the process of actively observing, analyzing, and gathering overall visual experiences and impressions of a space is Visual Survey (or visual analysis/assessment).
\[ \boxed{\text{Visual Survey}} \]