The correct answer is option 4, Dudhwa National Park has been developed as a Tiger Reserve.
Option 1, Bird sanctuary, is not the correct answer. While Dudhwa National Park does have a variety of bird species, it is primarily known for its population of tigers and is officially recognized as a Tiger Reserve.
Option 2, Deer park, is not the correct answer. Although Dudhwa National Park is home to many different species of animals, including deer, it is not specifically designated or developed as a deer park.
Option 3, Snake park, is not the correct answer. Dudhwa National Park does not have a specific focus on snakes. While there may be snakes present within the park, it is not a designated snake park.
Therefore, the correct answer is option 4, Tiger reserve. Dudhwa National Park is known for its conservation efforts and habitat for tigers, making it an important reserve for the protection of this endangered species.