Problem Solving, as Envisioned in Principles and Standards for School

Problem solving, as envisioned in Principles and Standards for School Mathematics and the Common Core State Standards for Mathematics, is most accurately described
by which of the following?

A) Problem solving should provide meaningful experiences that develop "strategies" that can be used to solve other problems.
B) Problem solving should be routine for primary and middle grades, with an emphasis on developing "strategies" in the high school grades.
C) Problem solving should be routine for primary grades, with an emphasis on developing "strategies" in the middle and high school grades.
D) The primary emphasis of problem solving should be to provide experiences with word ("story") problems at all grade levels.
E) Problem solving should be approached by assigning word problems at the end of each chapter or unit.