Step 1: Understanding the Question:
We need to identify which animal Sariska and Ranthambore are reserves for.
Step 2: Key Formula or Approach:
Match each named reserve to the wildlife conservation project it belongs to, since Indian reserves usually get their identity from the flagship species they were set up to save.
Step 3: Detailed Explanation:
Ranthambore National Park lies in Sawai Madhopur, Rajasthan, and became a Project Tiger reserve in 1973.
Sariska, in Alwar district of Rajasthan, is also a Project Tiger reserve, and it drew attention in the mid 2000s when its entire tiger population disappeared due to poaching, leading to a fresh relocation of tigers into the park starting in 2008.
Lions are protected only at Gir in Gujarat, so that option does not apply here.
Deer and bears are present in both parks as general wildlife, but they are not the reason these two reserves are famous.
Step 4: Final Answer:
Sariska and Ranthambore are tiger reserves, so the correct option is Tiger.