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: The transfer of heat in the atmosphere by winds that circulate between the equator and the poles is an example of  
 (A) radiation. (B) insulation. (C) convection. (D) conduction.

Answer: C


Question: When air rises over the open ocean, a low pressure system is formed. Which factor increases the potential of a low pressure system developing into a hurricane in the Northern Hemisphere?  
 (A) cool ocean currents circulating towards the equator (B) increased volcanic activity in the upper latitudes (C) cold air moving south from the North Pole (D) warm water temperatures in the tropics

Answer: D


Question: In the United States, windmills have been used for farming for hundreds of years. Which simple machine is the most important part of a windmill?  
 (A) lever (B) pulley (C) inclined plane (D) wheel and axle

Answer:
D