Which of the Following About Common Core State Standards Is

Multiple Choice

Which of the following about Common Core State Standards is true?

A) As of 2012, approximately half of all U.S.states have adopted these standards.
B) A goal of these standards is to bring greater rigor to academic expectations in school
C) All states must adopt the standards by the school year 2017-2018.
D) The standards are flexible so that individual states can change/adjust them as appropriate.