Step 1: Identify national symbols.
The Peacock (Pavo cristatus) was declared the national bird of India in 1963 for its rich cultural and religious symbolism.
Step 2: Cultural significance.
It symbolizes grace, beauty, and the vibrant heritage of Indian art and mythology.
Step 3: Conclude.
\[
\boxed{\text{Peacock (Option C) is the national bird of India.}}
\]