6596. All the characters in the novel are fictitious.

✅ The correct answer is option C.
Unreliable : not able to be relied upon.

Unbelievable : not able to be believed; unlikely to be true.

Unreal : imaginary or illusory.

Real : actually existing as a thing or occurring in fact; not imagined or supposed.

Fictitious : not real or true; imaginary or fabricated.

Synonym of Fictitious is Unreal