Hi Varun, terror is used to describe the fear or feeling of dread when you are anticipating something. Horror is used to describe the fear felt while experiencing something. Hence, in this case, horror is more appropriate.

Hi Aishwarya,

"Thrilling narrative" {thrilling: causing excitement; exhilarating; an intense feeling}. Although the focus is on fear, the phrase is often used to depict an element of horror {to a moderate degree}. "Terror" is extreme fear, which seems a bit odd {to be elicited by a thrilling narrative}. The sentiment does not match the context. I hope this helps!