In 2009, scientists suspected that the swine flu came into the United States from Mexico, and President Obama was asked why he didn’t close the U.S. border with Mexico. “Closing the border now,” he said, “would be like closing the barn door after the horses were out. I think our healthcare system is up to the task of taking care of the sick while we combat this disease and bring it to its knees.” Americans are the key to keep the swine flu from spreading. Health officials advised that the swine flu was a raging fire that could be stopped if more Americans would keep their hands washed, cover their mouths while coughing, and stay home from work or school if they were sick.

Which of these is an example of a metaphor?
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". . .key to keep the swine flu. . ."
". . .swine flu came into. . ."
". . .the swine flu was a raging fire. . ."
. . .keep their hands washed. . ."

". . .the swine flu was a raging fire. . ." is an example of a metaphor. This metaphor compares the swine flu to a raging fire to emphasize the urgency and seriousness of the situation.