When Juan and Carlos Were Little, They Were Very Similar

question 37

Multiple Choice

When Juan and Carlos were little, they were very similar. Juan was a bit more outgoing, and Carlos was a bit more shy, but they were otherwise alike. As they grew up, Juan went to more parties and made more friends. Carlos preferred to stay home to read, and had a couple of close friends. As adults, Juan is very social and Carlos is very reserved. Which of the following helps explain the change in their personalities over time?

• A) Cohort effects
• B) Nurture
• C) Nature via nurture
• D) Gene expression