At first glance, the Amazon logo looks like it is underlined by a smile but look closerthe smile is actually a kind of arrow! The smile at the bottom of the 'AMAZ' includes an arrowhead, starting at the A and ending with the Z. This conveys that they sell everything you need, from A to Z. The idea that an ad can be shown very quickly, online, on TV, or in the movies, so that it doesn't quite meet the threshold of consciousness, is said to be __________. The message is captured subconsciously, and marketers hope the message will compel action.

a. sensation

b. perceptual fluency

c. a perception map

d. subliminal advertising