The correct answer is option 'A', Rajasthan.

Vijay Prahar Exercise is a major military training exercise conducted by the Indian Army. It is aimed at enhancing the operational preparedness and battle readiness of the forces. The exercise involves the participation of various units and formations of the Indian Army, including infantry, artillery, armored, and air defense units.

Here is a detailed explanation of the Vijay Prahar Exercise of the Indian Army:

Introduction to Vijay Prahar Exercise:
- Vijay Prahar Exercise is a large-scale field training exercise conducted by the Indian Army.
- The exercise focuses on testing and refining the operational capabilities of the forces in a simulated battlefield environment.
- It aims to enhance the coordination and synergy between different units and formations of the Indian Army.

Objective of the Exercise:
- The main objective of the Vijay Prahar Exercise is to validate and improve the operational doctrines, battle concepts, and combat techniques of the Indian Army.
- It aims to enhance the capability of the forces to conduct offensive operations, defensive operations, and counter-insurgency operations.
- The exercise also provides an opportunity to test and evaluate the effectiveness of the equipment, weapons, and communication systems used by the Indian Army.

Location of the Exercise:
- The exercise was conducted in the state of Rajasthan.
- Rajasthan is the largest state in India, known for its vast desert terrain and extreme weather conditions. It provides an ideal environment for conducting large-scale military exercises.

Participants and Activities:
- The Vijay Prahar Exercise involved the participation of various units and formations of the Indian Army.
- Infantry units, armored units, artillery units, air defense units, and other supporting elements participated in the exercise.
- The exercise included a wide range of activities, including offensive maneuvers, defensive maneuvers, live firing exercises, combat simulations, and joint coordination exercises.

Significance of the Exercise:
- The Vijay Prahar Exercise plays a crucial role in enhancing the operational preparedness and battle readiness of the Indian Army.
- It helps in developing and refining the operational doctrines and tactics of the forces.
- The exercise also provides an opportunity to identify and address any shortcomings or gaps in the capabilities of the Indian Army.

In conclusion, the Vijay Prahar Exercise of the Indian Army was conducted in the state of Rajasthan. The exercise aimed at enhancing the operational preparedness and battle readiness of the forces through various activities and training exercises. The exercise provided an opportunity to test and evaluate the effectiveness of the equipment, weapons, and communication systems used by the Indian Army.