C137 Become a Master

"Ou, can you tell me what the black dot on the kitchen knife is?"

Wang Lin could not help but tremble. If the black dot was really harmful to the human body, then he had already come into contact with it many times. Was he going to die soon?

Although this idea was very strange, Wang Lin could not deny it.

"Start scanning!"

The Ou's voice sounded again. After waiting for 15 minutes