Answer:
An example of appropriate language for an essay about global warming is "Global warming is beginning to change weather patterns throughout the world."
Step-by-step explanation:
In order to write an essay using appropriate language, the author has to keep aways all the popular, casual, and informal expressions as well as the use of contractions or too personal approaches, from the given options, the first sentence is the one that uses a more formal and direct vocabulary since the other options are examples of casual and too personal ways to introduce a topic through the use of words an expressions such as "please take a moment", "big issue" or "Sometimes I worry¨.