B, the ruins of the once-thriving city feel dangerous and forbidding. This one is correct, since it mentions both the setting and the mood. The setting, being the once/thriving city. And the mood, being dangerous and forbidding
I find when the author leaves cliff hangers. Because you won't know what happens until the next chapter. Especially when you don't know what's going to happen it leaves a suspense in your chest until you read the next chapter. I like being surprised when I read it's actually fun.
