The intelligence test used most often today are based on the work of a Frenchman, Alfred B

i net. In 1905, Binet was asked by the French Ministry of Education to develop a way to identify those children in French schools who were too "mentally deficient (不足的)" to benefit from ordinary schooling and who needed special education. The tests had to distinguish those who were merely be hind in school from those who were actually mentally deficient.

The items that Binet and his colleague Theophile Simon included on the test were chosen on the basis of their ideas about intelligence. Binet and Simon believed intelligence includes such abilities as understanding the meaning of words; solving problems, and making commonsense judgements. Two other important assumptions also shaped Binet' s and Simon' s work. (1) that children with more intelligence will do better in school and (2) that older children have a greater ability than younger children.

Binet' s first test consisted of thirty tasks. They were simple things most children learn as a re ;suit of their everyday experiences. The tasks were arranged in groups, according to age. Binet decided which tasks were appropriate for a given age group by giving them first to a large number of children of different ages. If more than half of the children of a given age passed a test, it was considered appropriate for that age group.

The main purpose of this passage is to ______.

A．tell the origin of intelligence tests

B．explain the basic principle of intelligence tests

C．describe the changes in the content of intelligence tests

D．state the development of intelligence tests