Answer:
B, Psycho galvanometer
Step-by-step explanation:
A psycho galvanometer is one a device used to determine skin changes to elsctrical resistance in response to emotional stress. In advertising, the psycho galvanaometer is used to determine the acceptance or lack thereof of advertisements, products, etc. If there is a low resistance of the skin to electrical responses, then the advetisement is successful. If resistance is high, the advertisement is not successful and a new advertisement should be considered.