Which is not a factor that affects teenagers' ability to resist peer pressure and stand up for their own values?

The option which is not a factor that affects this is the number of friends they have. As long as they have at least one friend, people can be truly happy, so it doesn't really affect whether they will or won't be able to stand up to their peers. However, their self-asteem, their family backgrounds, and their role models will affect that a lot.