Answer:
The correct answer is All of the above .
Explanation:
When it comes to composing an email, we are expected to use a formal type of language. We should not write it in the same way that we write a text to a friend where we sometimes ignore the grammar rules.
The person who receives the email is probably a boss or a professional and that is why we should use Nouns, Adjectives and Adverbs, if required.
Therefore, the correct answer is "All of the above."