Using superlatives

[Fame]

Which sentence is correct/best:

1. Chick is strong, dog is stronger but the elephant is the strongest.
2. The chick is strong, the dog is stronger, the elephant is the strongest.
3. Chic is strong, dog is stronger but elephant is the strongest.

[David L.]

2. The chick is strong, the dog is stronger, but the elephant is the strongest. (referring to three particular animals

or

A chick is strong, a dog is stronger, but an elephant is the strongest. (referring to three examples of animals in the world).