Identify the main idea of the given statement and write it in one phrase.
Cats are intelligent animals and they often show it by problem-solving challenges.
Intelligence of cats.
Complete the following task based on the instruction and optional input provided.### Instruction:
Identify the main idea of the given statement and write it in one phrase.

### Input:
Cats are intelligent animals and they often show it by problem-solving challenges.

### Output:
Intelligence of cats.