The mood (or tone) of the prologue is considered as sombre, dark, macabre... since from the start we're being told that this story is going to be a story of love, death and loss.
Answer:
A thesis statement:
tells the reader how you will interpret the significance of the subject matter under discussion. is a road map for the paper; in other words, it tells the reader what to expect from the rest of the paper. directly answers the question asked of you
I'm pretty certain the correct answer is a supporting sentence