For CLAT UG Legal Reasoning, you can use some popular books that cover concepts topic-wise with examples and practice exercises. A few recommended books are:

• Legal Awareness and Legal Aptitude by A.P. Bhardwaj
• Objective Legal Aptitude by R.S. Agarwal
• Legal Awareness and Legal Reasoning by Pearson
• The Pearson Guide to the CLAT by Harsh Gagrani
• Important Judgments That Transformed India by Alex Andrews George

For a detailed guide on these books and how to use them effectively, you can check this Careers360 article: https://law.careers360.com/articles/clat-legal-reasoning-books