instruction:
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:
A large number of species on Earth became extinct during a short time period about 65 million years ago. Based on this pattern of extinction, which is the most likely cause?  
 (A) gradual climate change (B) continued climate stability (C) sudden global climate change (D) gradual ecosystem succession
answer:
C


question:
Genes are located on chromosomes which are composed of  
 (A) DNA. (B) RNA. (C) ATP. (D) ADP.
answer:
A


question:
Which type of light can cause severe eye damage if it is viewed directly?  
 (A) an infrared light (B) a laser beam (C) an incandescent light (D) a Bunsen burner flame
answer:

B