Which book is best for clearing concepts?

Hi varun which part of india are you from?
For quant i suggest use Maharashtra SSC/HSC 10th std to 12th std text books , the most amazing books to understand the basics. It teaches in elementary style and has a lot of solved examples.
I would also recommend MGMAT quant books they are also really good for quant concepts.(though i have personally used only 1 book, my friend who was weak in quant used those books and she liked it a lot and highly recommends it)
Also if you wana learn tons of tips and tricks for quant(these are not covered in mgmat, use Arun Sharma's CAT quantitative aptitude - before my gmat i just went through the formulaes and solved examples in that book - a warning though this has some content that is outside the gmat so if u wana know which to study and which not to get in touch with me..(PM me ill give u my phone no)
One more book which i really liked is the gmat club math book - freaking got all formulaes in there, i jst went through the first 10 pages in detail and jst went throught the other pages really fast - real good compliation of formulaes this book is a must bro learn it from cover to cover if u dont know the formulaes already.

But at the end of the day if your weak in quant and want to improve that part of your gmat preparation just choose one book as below and practise practise practise(the only proven way to improve):-
If you are short on time - Gmat quant book(cover to cover) & practise from OG all problems with wrong problem analysis
If you have decent amount of time - Mgmat guides and practise from OG all problems with wrong problem analysis.
If you have tons of time - Use Maharashtra books to understand basics, then use CAT books for tips tricks and how to think through tough problems then practise from OG all problems with wrong problem analysis.