The author develop the idea that flying takes skill, "By specifying that pilots must take classes and practice flying under various conditions, the author highlights the expertise required to fly a plane."
What is skill?
Skill is the proficiency in a particular task.
Because the author specifies that pilots must take classes and practice flying under various conditions, the author highlights the expertise required to fly a plane. They should take their training very seriously, which will make them understand the true value of their learning. All this develops the idea that flying takes skills. As there is much death due to pilot error, so operate the airplane safely.
Hence the correct option is, D) "By specifying that pilots must take classes and practice flying under various conditions, the author highlights the expertise required to fly a plane."
To know more about skill:
https://brainly.com/question/24718712
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