Hi Riyashahid! There is no specific best book for the judiciary exam. But there are books given as follows which you can go through for entrance examinations:
Study Package for Clat and LLb by A P Bhardwaj
Universal's Guide to CLAT & LL.B. Entrance Examination2018-2019
Compulsory English for Civil and Judicial Services
I hope this information has helped you:)
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