Passage 1 Questions 1 to 5 arebased on the following passage:The first year of school in America, knownas kindergarten, usually begins between the ages of five and six. Among richcountries such a late start is very strange. President Obama believes it is an economic and social problem; hiseducation secretary goes as far as to say that it is "morally wrong".This statement has some support, as it is clear from research into vocabulary that youngsters from poorfamilies enter kindergarten well behind those from rich families—a disadvantagethat usually lasts a lifetime. Children from households on welfare knew 525words by the age of three, while the children of professionals had mastered1,116.(76) Pre-school can help close this gap. So in aspeech last month, Mr. Obama called for apartnership between the federal government and the states to expand it to everyAmerican child. It later became known that "every" meant those whocome from families with incomes of up to 200% above the poverty line—equal toan income of $47,000 for a family of four.(77) Some critics say that sending children to school at the age of four does not work. The evidence suggests otherwise. For example, on March 20thnew results were announced from a study of 9tol1yearolds in New Jersey. Thisreport found that disadvantaged children who had attended pre.school had betterliteracy (读写能力), language, maths and science skills. And two years of pre.kindergartenwere better than one.Some studies also follow the effects ofearly learning over lifetimes, such as its effect on crime rates and otherfactors that may eventually burden society. Critics have singled out a government scheme called Head Start, created in 1965,which provides poor households with a range of services including school.basedearly education. The phrase "single out" in the lastparagraph means （）.

A. choose
B. think about
C. count
D. depend on