Answer:
The correct answer is option B.
Step-by-step explanation:
The ancient Chinese were not willing to share the art of silk production with other cultures. It was a closely guarded secret for a long period. Though silk was traded through the silk route, the method of its production was not known to the world.
Other cultures assumed it also came from a plant, like other fabrics. Any person who tried to reveal the secret was given the death penalty.