Correct Response: C. Student portfolios should be able to include a wide variety of student work products. This requires compatibility with a variety of file types including graphic, audio, and video documents. A is incorrect because only the teacher should have such administrative privileges. B is incorrect because any peer assessment needs to be well controlled by the teacher, and should not be as simplistic as up/down votes. D is incorrect because this type of access is not necessary and could lead to unsupervised or unauthorized access.