What the story or person is mainly talking about.
It's D! I read this book last year and Cassie wants to gain her trust so she will tell her things and then later betray her.
The answer would be the second option
A soliloquy, similar to a monologue, is a speech, but it's a speech that one gives to oneself regardless of whose hearing, it is used as a tool to better help the audience to understand what the character is feeling internally. An example of one, and perhaps the most famous is this one:
To be, or not to be, — that is the question: —
Whether 'tis nobler in the mind to suffer
The slings and arrows of outrageous fortune
Or to take arms against a sea of troubles,
<span>And by opposing end them? (etc.)</span>
While there are many different sound devices that can be used in poetry, such as near rhyme (sounds are similar but not exact), alliteration (same beginning sounds), this one is onomatopoeia. Onomatopoeia is using words to suggest a sound. This can also be words like whispering, sizzle, thump, clang, etc. Using onomatopoeia allows you to imagine what it would sound like if you were present (this is part of imagery).
