Although the Intellectual Gains from Head Start Have Not Persisted

Although the intellectual gains from Head Start have not persisted once the children entered regular classrooms, it is important to remember

A) that today's children spend more time watching television and using the Internet than they spend in school, thus, school can only be responsible for some of one's IQ gains.
B) that even a high-quality Head Start program can provide stimulation for only a few hours a day over the span of a few years.
C) that early childhood education programs are worthwhile for many social, developmental, and cultural reasons other than raising IQ scores
D) all of these reasons.