Final answer:
An eye camera is the correct tool for determining which part of a magazine ad is noticed first by viewers; it tracks eye movements to measure visual attention, unlike a galvanometer or other unrelated devices.
Step-by-step explanation:
To determine which part of a magazine ad is noticed first by the viewer, the appropriate electronic/mechanical tool to use would be an eye camera. An eye camera is a device that tracks where the viewer’s gaze lands and how it moves across a visual field. This allows researchers to understand visual attention and interest. In contrast, devices like an optical scanner, galvanometer, people meter, and visual analyzer serve other specific functions not directly related to tracking eye movements. For instance, a galvanometer measures electrical current and would not be helpful in understanding which part of an ad is seen first.
Electronic detectors like an eye camera have eliminated the quirks of human memory, similar to how modern detectors in astronomy permanently record information from the cosmos, improving upon the human eye as the initial detector. In the field of advertising and marketing, utilizing such technology provides an empirical approach to gauging viewer engagement and the effectiveness of visual elements within an ad.