The answer is D: After some soul-searching and introspection, Peter knew that it was time for him to move on.
Introspection is the action of self-reflection, that is to say, internal observation of one´s own state of mind. This kind of intra-personal observation can yield insights about one´s own corporeal, sensitive, cognitive and emotional states. It is contrasted to external observation of objects as different and external to the mind.
Many examples are :
<span>Belief in Others
</span>Caring<span>
Commitment
Dedication
</span>
They are definitely not synonyms, that would mean they mean the same thing wich they definitely do not. They are antonyms.