You will be given a definition of a task first, then some input of the task.
You are given a science question (hard-level) and four answer options (associated with "A", "B", "C", "D"). Your task is to find the correct answer based on scientific facts, knowledge, and reasoning. Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D'. There is only one correct answer for each question.

Golden rice is a transgenic plant that produces rice with high levels of vitamin A. The rice would help people improve the nutrition in their diets. However, some people are concerned about the effects the transgenic rice might have on native plants. Which words best characterize these concerns?
(A) practical and economic (B) economic and ecological (C) ecological and ethical (D) ethical and practical
Output:
C