Answer:
Preferential looking technique
Explanation:
Through the preferential looking technique, the perceptual abilities of infants who are unable to speak are evaluated. If the stimulants are different, generally, the infants would prefer to focus on the more interesting stimulant than on the less interesting stimulant, as long as the two stimulants are shown at the same time. It is assumed that the stimulant which is observed more frequently is the one the infant prefers. The technique reveals or shows the capacity the infant has to discriminate between stimulants.