Read the following passage. Karate is a martial art. It was first developed in Japan. Today, people practice karate around the world. Karate develops strengths and discipline. Many children start to learn karate at the age five or six. Karate is the best answer to common health problems. People can manage their injuries and illnesses by practicing this sport.

Which sentence from the passage shows the author's bias?

A. It was first developed in Japan.

B. Many children start to learn karate at the age five or six.

C. Karate is the best answer to common health problems.

D. Today, people practice karate around the world.

Please help me out over here.