Advice to select the right CR book to meet my requirement...

Hi arijitdatta,

What you're looking for and what you actually need might be different things. The GMAT is a consistent, predictable Exam - as such, the style of the questions and logic behind how they are written is consistent. The logic behind CR questions comes down to a limited number of standard concepts, but the 'packaging' will vary from question to question. As an example, the logic behind an advanced 'causality' CR is the same logic that applies to an 'easy' causality CR - however, the way the question is worded, the types of wrong answer choices, etc. would be more difficult by comparison. If you're not comfortable using causality logic on a lower-level question, then you'll have a difficult time using it on an upper-level one. This is all meant to say that you probably don't need to focus on 'hard' prompts right now - you have to make sure that you understand the central ideas behind how all CR questions are written, so that you can approach ANY CR prompt in an efficient way.

You've defined your score goal, but I'd like to know a bit more about your overall studies so far:

1) How long have you studied?
2) What materials have you used?
3) How have you scored on each of your CATs (including the Quant and Verbal Scaled Scores)?

4) When are you planning to take the GMAT?
5) When are you planning to apply to Business School?

GMAT assassins aren't born, they're made,
Rich