Answer: Option B
Step-by-step explanation:
The normal cells when grown in a nutrient medium starts growing in into the petri dish. The cells keep on growing and when the bottom layer of the plate is filled with the cells then the cells in the petri dish stops growing. This is because the cells observes the contact of one cell with another.
This is known as contact inhibition which does not allows the growth of one cell upon another. Contact inhibition is a part of cell signaling in which there are check points that allows the optimum growth of the cells.
This is a mechanism which helps the cells in optimum growth. This helps in preventing the cell from developing tumor by dividing uninterruptedly.