Which wetland is famous for migratory birds in Rajasthan?

The correct option is Keoladeo National Park.

Explanation:
Keoladeo National Park, formerly known as the Bharatpur Bird Sanctuary, is a famous avifauna sanctuary in Bharatpur, Rajasthan, India. It hosts thousands of birds, especially during the winter season, and is renowned globally as a wintering ground for migratory waterfowl, including rare species like the Siberian Crane.

Let us look at the other options for clarity:
- Dal Lake: Located in Srinagar, Jammu and Kashmir.
- Chilika Lake: Located in Odisha; it is a brackish water lagoon, famous as a migratory bird site, but not in Rajasthan.
- Loktak Lake: Located in Manipur, famous for its floating phumdis.