The answer is A. With is a preposition, thus anything coming after that is a prepositional phrase.
I'd say b, but I feel this could be somewhat open to interpretation.
It demonstrates that Nora is considering leaving her children.
The text states: Nora: Do you think they would forget their mother if she went away altogether? This implies that Nora is thinking about a scenario where she leaves her children behind. Hope I helped!
Do you have the paragraph if you do look for an evidence to see if it can support your answer I swear I would help if I have read it all and work get you the answer