TASK DEFINITION: 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.
PROBLEM: When the cardboard cone of a radio speaker vibrates, it produces a sound in the air around it. The cone produces this sound by transferring which of the following to the air around it?  
 (A) heat (B) current (C) wave motion (D) magnetic force

SOLUTION: C

PROBLEM: Which of these would help to prevent infections from occurring in small cuts and scrapes?  
 (A) apply a cold ice pack (B) raise the injured area (C) apply pressure to stop bleeding (D) wash the area with warm, soapy water

SOLUTION: D

PROBLEM: A bird called a ptarmigan has feathered feet. The feathers on the feet of the ptarmigan are most helpful when this bird ___.  
 (A) digs up food (B) walks in deep snow (C) climbs rocky cliffs (D) runs under bushes

SOLUTION:
B