Hi Nidhi. I believe you mentioned previously that you have Mike Griffiths's book, PMI-ACP Exam Prep Second Edition. The book covers Agile Contracting in Chapter 2 Value -Driven Delivery, pages 123 - 127.
The contracts he covers in the book are: DSDM Contract, Money for Nothing and Change for Free, Graduated-Fixed Price Contract, Fixed-Price Work Packages, and Customized Contract. Reading that section will answer your questions and will prepare you to answer any contract related question on the test.
Also, if memory serves me correctly the OSP Exam Simulator includes several contract questions to help with your studies.
Good luck!