Is PMBOK Guide Sufficient to Clear the PMP Exam?

Generally speaking, the answer is 'no'. There are topics on the PMP exam that aren't even covered in the PMBOK Guide. So, you cannot completely rely on the PMBOK Guide for your preparation. Usually, a combination of a good training program (for 35 Contact Hours of PM Education), the PMBOK Guide, a good PMP exam prep guide, and free resources available on the web are what you need to pass the PMP exam.