Answer:
The correct option is B) Ethylene is produced at a higher rate, causing rapid division of cells in darkness.
Step-by-step explanation:
The root cells are present in the ground where there is darkness. When ethylene is produced at a faster rate and it stimulates the division in darkness, this means that it will stimulate the division of the root cells. As a result, the growth of root cells will occur. Hence, option B is correct.
Other options, like option C, is not correct because when auxins will accumulate at the darker sides of the leaves, growth will occur on the other side of the leaves. It will not affect the growth of roots.