Yes, solving previous years question papers can help in improving memory retention for the Zoology optional subject. Here's how:

1. Reinforcement of Concepts:
Solving previous years question papers enables you to revisit and reinforce the concepts you have learned. By attempting questions related to various topics in Zoology, you engage in active recall of information, which strengthens your memory and understanding of the subject.

2. Identification of Important Topics:
Going through previous years' question papers helps you identify the important topics and areas of focus in Zoology. You can analyze the frequency of questions from different chapters or themes and prioritize your study accordingly. This approach allows you to allocate your time and efforts more effectively.

3. Familiarity with Exam Pattern:
By solving previous years' question papers, you become familiar with the exam pattern and the types of questions asked in the Zoology optional subject. This helps you develop a better exam strategy and prepares you for the format and structure of the actual exam. You can also understand the weightage given to different topics and adjust your preparation accordingly.

4. Time Management:
Practicing previous years' question papers helps you develop time management skills, which are crucial during the actual exam. By solving the papers within the specified time limit, you learn to allocate time to different sections and questions. This not only enhances your efficiency but also reduces anxiety during the exam.

5. Application of Knowledge:
Solving previous years' question papers allows you to apply the theoretical knowledge you have acquired in a practical context. It helps you understand how to integrate different concepts and apply them to solve complex problems. This enhances your problem-solving abilities and critical thinking skills, which are valuable in the Zoology optional subject.

6. Confidence Building:
Regular practice of previous years' question papers builds your confidence as you become familiar with the question patterns and gain proficiency in answering them. It reduces exam-related stress and boosts your self-assurance, leading to better performance in the actual exam.

In conclusion, solving previous years' question papers is an effective strategy to improve memory retention for the Zoology optional subject. It reinforces concepts, identifies important topics, familiarizes you with the exam pattern, enhances time management skills, promotes the application of knowledge, and builds confidence. Make sure to incorporate this practice into your overall preparation strategy for a successful performance in the UPSC exam.