All of the Following Have Been Cited as Possible Explanations

All of the following have been cited as possible explanations for low achievement scores among American students, except:

A) teachers do not spend enough time on basic instruction, and very little time is spent on writing.
B) students do not take advanced courses when they are offered.
C) parents do not encourage academic pursuits at home.
D) students spend too much time involved in extracurricular activities.