Final answer:
Infants undergo symbolic processing through activities like pretend play.
Step-by-step explanation:
Symbolic processing is a cognitive ability that allows infants to use symbols, such as words or images, to represent objects or concepts. One primary example of symbolic processing that infants undergo is pretend play. During pretend play, infants use objects to represent other objects or engage in imaginative scenarios. For example, a child may use a block as a phone or pretend to be a doctor using a pretend medical kit.