Trishakti Prahar Exercise:
The Trishakti Prahar Exercise is a joint military exercise conducted by India, Australia, and the United States. It aims to enhance cooperation and interoperability between the three countries' armed forces. The exercise focuses on joint planning, training, and execution of a wide range of tactical operations in a multinational environment.

Statement 1: It is a multilateral military exercise involving India, Australia, and USA - Correct
The first statement is correct. The Trishakti Prahar Exercise involves India, Australia, and the United States as participating countries. This exercise reflects the growing strategic partnership and cooperation between these nations. It provides an opportunity for the armed forces of these countries to work together and learn from each other's experiences and capabilities.

Statement 2: It seeks to serve as a platform to evaluate the effectiveness of modern warfare technologies - Incorrect
The second statement is incorrect. The primary objective of the Trishakti Prahar Exercise is not to evaluate the effectiveness of modern warfare technologies. Instead, it focuses on building and enhancing joint operational capabilities, coordination, and interoperability between the participating countries. The exercise involves various training scenarios and tactical operations to improve the overall readiness and effectiveness of the armed forces.

Significance of Trishakti Prahar Exercise:
- Strengthening Strategic Partnerships: The exercise helps in strengthening the strategic partnerships between India, Australia, and the United States. It promotes mutual understanding, trust, and cooperation among the participating countries.
- Enhancing Interoperability: By conducting joint military exercises, the armed forces of these countries learn to operate together effectively in a multinational environment. This enhances their interoperability and coordination during real-world operations or humanitarian assistance missions.
- Sharing Best Practices: The exercise provides a platform for sharing best practices, tactics, techniques, and procedures among the participating countries. This enables them to learn from each other's experiences and improve their own operational capabilities.
- Promoting Regional Security: The Trishakti Prahar Exercise contributes to promoting regional security and stability. It sends a strong message of deterrence to potential adversaries and demonstrates the commitment of the participating countries to maintain peace and security in the region.
- Strengthening Military Diplomacy: Joint military exercises like Trishakti Prahar also strengthen military diplomacy between the participating nations. It allows for high-level interactions, exchanges of ideas, and building personal relationships among the military leadership, which can further enhance cooperation and understanding.

Therefore, the correct answer is option 'B' - Statement 2 is incorrect.