Answer: C: "These beautiful creatures are amazing to watch."
Explanation: Bias is where an author adds their personal opinion on a topic such as this one on monarch butterflies. Sometimes, authors use bias and it gets away from the facts and the credibility that the topic should bring. In option C, the words "beautiful" and "amazing to watch" steers the reader away from the actual topic with their personal opinions. The other options from the passage include facts about the monarch butterflies and resisting the urge to add comments about how beautiful or interesting they are.
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