You are given a science question (easy-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.
--------
Question: Which characteristic best identifies a pure substance?  
 (A) shape (B) texture (C) melting point (D) state of matter

Answer: C


Question: Joann repeatedly overfed the fish in the pond behind her house. The nitrates from the excess food contributed to an overgrowth of algae. To correct the problem, Joann added more plants to the pond. How will adding more plants help?  
 (A) The plants make the pond look beautiful. (B) The plants will camouflage the green algae. (C) The plants will compete with algae for nutrients. (D) The plants will provide all the food for the fish.

Answer: C


Question: The disruption of which cell function leads to gene mutations that result in cancer?  
 (A) protein synthesis (B) RNA transcription (C) RNA translation (D) DNA replication

Answer:
D