Finding question papers for the optional subject of entomology from different entrance examinations can be a challenging task. However, there are a few strategies that you can follow to locate these question papers. Here's a detailed explanation of how you can go about it:

1. Official Websites:
Check the official websites of the respective entrance examinations. Many organizations, like UPSC, release previous years' question papers on their websites. Look for the specific entrance examination you are interested in and search for the entomology optional subject question papers.

2. Online Forums and Communities:
Join online forums and communities related to entomology or the specific entrance examinations you are targeting. These platforms often have discussions and resources shared by aspirants who have appeared for the exams in the past. Engaging with the community and asking for question papers can be helpful in obtaining the desired materials.

3. Coaching Institutes:
Contact coaching institutes that specialize in entomology or offer guidance for the entrance examinations you are preparing for. These institutes usually have a collection of question papers from previous years that they may share with their students or provide for reference. Enrolling in such institutes can grant you access to their question paper archives.

4. Online Document Sharing Platforms:
Explore online document sharing platforms, such as EduRev, where students and educators upload study materials, including question papers. These platforms often have a wide variety of resources available for download, making it easier to find question papers for the entomology optional subject.

5. Social Media Groups:
Join social media groups and pages dedicated to entomology or UPSC preparation. These communities are usually active and may have members who can share question papers or direct you to the relevant resources.

Remember, it is essential to verify the authenticity and reliability of the question papers you find. Cross-referencing with official sources or consulting with subject matter experts can help ensure the accuracy of the materials you use for your preparation.

In conclusion, finding question papers for the entomology optional subject from different entrance examinations requires a combination of online research, engagement with communities, and utilizing available resources. The key is to explore official websites, online forums, coaching institutes, document sharing platforms, and social media groups to increase your chances of obtaining these question papers.