Irene conducts a laboratory experiment to test the memory of children. She rapidly reads out a list of colors to three children aged 4, 6, and 13 years. The children are then asked to repeat the names of the colors. Irene notices that the 6-year-old and the 13-year-old are able to recall more colors than the 4-year-old. This experiment illustrates that

Memory span varies in every person.

Explanation:

Memory span is the ability of mind to determine the items and things by repeating it in the same way and order as they were presented .This ability varies from one person to another person for depicting extent of memory.It describes performance in problem solving , cognitive tasks, general reading etc .

According to the question, experiment of Irene is describing that memory span is different in 4 year old, 6 year old and 13 year old children because of age and ability.Thus, each of them is able to repeat color names as per varying memory span.