Answer: The word 'manifestations' means D. visible expressions of something internal.
Step-by-step explanation: The word 'manifestation' is a noun used to refer to an action or situation that embodies in a clear way an abstract thing. Therefore, a manifestation is an expression that shows something. In the sentence provided, the word 'manifestations' is used to make reference to the sign of an abstact thing: the feeling of guilt. Therefore, in the context of this sentence, the manifestations are visible expressions of something internal.