I agree with the above post.
There is a misconception as to the purpose of the destroyer, that it's only a book with hundreds of questions. Although that is one great component of the study guide, it is the comprehensive detailed review of all the topics that students are interested in. The key is to not understand why choice C is the correct answer. It is knowing why A,B,D and E are wrong. Once you understand all the correct and incorrect choices by reading the explanations in the solutions section, the material will seem that much more comprehensible and within reach.
Best of Luck,
dantheman2007