The complete adjective clause in the sentence is F. that I have prepared.
An adjective clause usually starts with who, whom, when, where, why, that or which. Most often it provides more information and description; however, it will not change the meaning of the sentence.
When your text states that communication is unavoidable, it means that people will probably associate meaning to your actions, even when you don not intend to speak of something.
Well, but he did have some hardships.
