The answer will most likely be A!
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.
The Spy, written by James Fenimore Cooper, mainly took place in one setting. That setting was what they characters referred to as "the Locust." The Locust was the summer home of the Wharton's. They migrated to the home to try and avoid the war between the British and America and having to take sides.
"The prince of Cumberland! That is a step
On which I must fall down, or else o'erleap,
For in my way it lies. Stars, hide your fires;
Let not light see my black and deep desires.
The eye wink at the hand, yet let that be
Which the eye fears, when it is done, to see."
The foreshadowing referenced within the aside is that Macbeth is talking about stepping over Malcolm or giving up. It's foreshadowing because Macbeth kill's Malcolm's father, Duncan.