Give me name of some best books for preparation of UPSC Preliminaries Political science examination ?

Here I am giving you name of some best books for preparation of UPSC Preliminaries Political science examination below :

Polity (Indian Constitution)
An Introduction to the Constitution of India by D.D. Basu
Our Constitution by Dr. Subhash Kashyap

Political Science 1st Edition
Author: N. D. Arora



IAS - Civil Services Main Examination - Political Science Paper I & II : Chapterwise Explanatory Questionnaire 1st Edition
Author: Kumud Ranjan Singh