If a Colleague Said That Her Approach to Classroom Assessment

If a colleague said that her approach to classroom assessment was reflected by the phrase "assessment as learning," what would she mean?

A) Students learn from her assessments what subjects they have an aptitude for.
B) She learns how much of what she taught was learned by various students.
C) She learns which of her lessons was successful and which were not.
D) Students learn what they have and have not learned and she learns how successful her teaching was.