Answer: A. Research into a phytochemical from a plant which might inhibit cancer development.
Explanation:
The chemoprevention is a process of utilization of chemical formulations such as medication, supplements and vitamins to the stop the growth of cancer cells. This is necessary and important for people which are at high risk of developing cancer.
The research for the phytochemical derived from the plants can be an example of chemoprevention as this will help in inhibiting the cancer development.