When monarch butterflies arrive in Mexico from Canada and the United States, they converge on oyamel fir trees. The trees provide shelter to monarch butterflies they are also essential to the communities that surround the forests. In the past, residents used the wood for cooking and heating, but recently, they have began to sell it in order to support their livelihoods. As a result of logging oyamel fir trees, the habitat of the monarch butterfly population has shrunk.
What is the main idea of this passage?
Explanation
Answer [A]: The main idea of this passage is that an increase in logging of the ovamel fir tree has diminished the winter habitat for monarch butterflies, and, consequently, decreased the population of the butterfly. Monarch butterflies do migrate from Canada and the U.S. to Mexico, and increased logging has been brought on by economic need. However, the point of the passage is to make the connection between this increased logging and the decrease in butterfly population.
