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.

[Q]: A bird eats a brightly-colored insect that tastes bad. The bird avoids preying on this type of insect again. This example is best described as  
 (A) a physical characteristic. (B) a learned behavior. (C) an inherited behavior. (D) an adaptation.
[A]: B


[Q]: In an accurate diagram of the solar system, which object would be shown closest to Earth?  
 (A) the Moon (B) the asteroid belt (C) Mars (D) Saturn
[A]: A


[Q]: Which has the greatest effect on aiding the movement of blood through the human body?  
 (A) tension (B) friction (C) density (D) gravity
[A]:
D