Instructions: In this task, you're given an article and an answer. Your task is to generate the fill-in-the-blank question for this answer based on the given article. The blanks are always at the end of the question, and can be filled with more than one word or phrase.
Input: Article: Throughout the world, boys and girls prefer to play with different types of toys. Boys typically like to play with cars and trucks, while girls typically choose to play with dolls. Why is this? A traditional sociological explanation is that boys and girls are socialized and encouraged to play with different types of toys by their parents, peers, and the "society". Growing scientific evidence suggests, however, that boys' and girls' toy preferences may have a biological origin. In 2002, Gerianne M. Alexander of Texas A&M University and Melissa Hines of City University in London surprised the scientific world by showing that monkeys showed the same sex typical toy preferences as humans. In the study, Alexander and Hines gave two masculine toys (a ball and a police car), two feminine toys (a soft doll and a cooking pot), and two neutral toys (a picture book and a stuffed dog) to 44 male and 44 female monkeys. They then assessed the monkeys' preference for each toy by measuring how much time they spent with each. Their data showed that male monkeys showed significantly greater interest in the masculine toys, and the female monkeys showed significantly greater interest in the feminine toys. The two sexes did not differ in their preference for the neutral toys. If children' s toy preferences were largely formed by gender socialization, as traditional sociologists' claim, in which their parents give "gender appropriate" toys to boys and girls, how can these male and female monkeys have the same preferences as boys and girls?They were never socialized by humans, and they had never seen these toys before in their lives.
Answer: are largely formed in later life
Output:
Traditional sociologists believe boys' and girls' toy preferences _