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:
Which of the following units best represents the density of an object?  
 (A) kg (B) hr (C) m/s^2 (D) g/cm^3
answer:
D


question:
Which of these is an inherited behavior?  
 (A) a seal balancing a ball (B) a dog getting the newspaper (C) a spider spinning a web (D) an ape using sign language
answer:
C


question:
Vascular plants have tissue called xylem. Which of these is transported by the xylem?  
 (A) food made by the plant (B) water needed by the plant (C) pollen for plant reproduction (D) carbon dioxide for photosynthesis
answer:

B