In 1989, biologists Ana Soto and Carlos Sonnenschein at Tufts University in Massachusetts were studying how the hormone estrogen regulates the growth of cells in the female reproductive system, specifically in human breast tumor cells. Suddenly, the cells in plastic containers were growing without the presence of estrogen. Which of the following statements are true about this experiment?

A. Estrogen was discovered as a "trade secret" ingredient in the creation of the plastic test tubes.
B. Estrogen was identified as the chemical used to manufacture hard plastics, like the plastic cell culture tubes.
C. Estrogen activates mitotic division in these cells.
D. Nonylphenol mimics the action of estrogen.
E. Nonylphenol in the plastic tubes of the cell culture activated mitotic division.

C. Estrogen activates mitotic division in these cells.

D. Nonylphenol mimics the action of estrogen.