Which One of the Following Is the Major Rationale Underlying

Which one of the following is the major rationale underlying a mastery learning approach to instruction?

A) Students have greater self-esteem when they can all work at the same pace.
B) All students should be able to achieve at grade level.
C) Students should learn one topic well before moving on to a more difficult one.
D) Students construct their own understanding of the world from the information they receive.