Although Books Can Be Good Sources for a Literature Review

Although books can be good sources for a literature review, the material in them should be considered with caution because:

A) books do not contain original reports of research.
B) the review process that books undergo may not be as rigorous as the process that articles in scientific journals undergo.
C) the authors of books are not as highly respected as the authors of journal articles.
D) All of the answers are correct.