Question

long speech given by one character alone on stage; this type of speech reveals the character’s inner life, thoughts, struggles, thought aloud for the benefit of the audience.
foil
monologue
aside
soliloquy

Explanation:

A soliloquy is a long speech by a single character alone on stage, revealing their inner thoughts, struggles, and is spoken aloud for the audience. A foil is a character that contrasts another, a monologue can be to others, and an aside is a short comment to the audience/another character, not a long self - revealing speech alone.

Answer:

D. soliloquy