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:
All of the following can become fossils except  
 (A) bones. (B) shells. (C) teeth. (D) rocks.
answer:
D


question:
Fertilizers added by farmers to the soil contain high amounts of nitrates. How do fertilizers affect the nitrogen cycle?  
 (A) More nitrates are available for plants to absorb. (B) More nitrates are available for animals to eat. (C) More nitrogen gas is released into the atmosphere. (D) More nitrogen is converted by bacteria into nitrates.
answer:
A


question:
Which statement describes a function of bones in mammals such as dogs and horses?  
 (A) Bones provide protection for organs in the body. (B) Bones send messages to the brain to move the muscles. (C) Bones carry oxygen-rich blood throughout the body. (D) Bones connect the brain and the spinal cord.
answer:

A