Philosophy Optional is a popular subject for the Union Public Service Commission (UPSC) examination, and there are several coaching institutes and online courses that offer quality study material for this optional subject. These resources provide comprehensive coverage of the syllabus and help students in their preparation for the examination. Some notable coaching institutes and online courses that offer quality study material for Philosophy Optional are:

1. Vision IAS: Vision IAS is a renowned coaching institute that offers a dedicated program for Philosophy Optional. They provide comprehensive study material that covers the entire syllabus, including the major philosophers, Indian philosophy, Western philosophy, and contemporary issues. Their study material is well-structured and designed to help students grasp complex philosophical concepts easily.

2. Drishti IAS: Drishti IAS is another popular coaching institute that offers study material for Philosophy Optional. Their study material is prepared by subject experts and covers all the relevant topics in a concise and easy-to-understand manner. They also provide practice questions and previous year's question papers to help students improve their answer writing skills.

3. EduRev: EduRev is an online learning platform that offers a wide range of study materials, including for Philosophy Optional. They have a dedicated section for Philosophy Optional, where students can access comprehensive notes, video lectures, and practice questions. The study material is designed to cover the entire syllabus and is regularly updated to incorporate any changes in the UPSC examination pattern.

4. ForumIAS: ForumIAS is a popular online platform for UPSC preparation, and they also offer study material for Philosophy Optional. Their study material includes comprehensive notes, reference books, and previous year's question papers. They also provide guidance and support through their online forum, where students can interact with fellow aspirants and mentors.

5. InsightsIAS: InsightsIAS is another online platform that offers study material for Philosophy Optional. Their study material is designed to cover the entire syllabus and is supplemented with practice questions and answer writing guidance. They also provide regular updates and current affairs material to help students stay updated with the latest developments in the field of philosophy.

In conclusion, there are several coaching institutes and online courses that offer quality study material for Philosophy Optional. These resources provide comprehensive coverage of the syllabus and help students in their preparation for the UPSC examination. Some notable options include Vision IAS, Drishti IAS, EduRev, ForumIAS, and InsightsIAS.