How are choices presented in the novel Frankenstein by Mary Shelly?

Asking how Shelley "presents" choices is vague, and could
be treated in many ways, so I'm not sure I'll hit what you or your teacher are after.  I
can detail two aspects of the choices that Frankenstein makes in the novel named after
him, though.

First, Victor often thinks he is making the
high-minded, correct decision.  When he chooses to make the creature, he thinks he is
furthering science and contributing to great discoveries.  He is doing what no on else
can do.  When he chooses to destroy the female creature he thinks he is standing up to
and against evil--the creature.  He thinks he is saving the world by not trusting the
creature to keep his word and not wreak havoc on humans with his new partner.  He thinks
he knows more than others and he knows what is moral.  But his decisions turn out to be
immoral and unjust.

Second, but related, is the
irresponsibility of his decisions.  The two decisions mentioned above are irresponsible,
of course, as is the decision to not recognize and nurture the creature he fathers. 
Without nurture, the creature turns into a monster.  Victor owns much of the
responsibility for this.  His decision to leave his wife alone on their wedding night is
also irresponsible.  He would have fought the creature and risked his life for her, but
his self-centeredness prohibits him from considering her as at risk.  He sees only
himself as the focus of the creature's plans.      

Again,
I don't know if what I've written is the kind of thing you were after, but I hope I came
close.