What organ would blood clots from the lower legs have to pass through to get to the lungs?

Which statement correctly describes a way that mutations increase the likelihood that a species will survive in a changing environment

I’m stuck on this question cuz i’m stupid sksksksk

Jason adds the antibiotic penicillin to a bacterial culture. the bacteria develop genetic modifications in their genome, which gives them resistance to the antibiotic penicillin. what caused this genetic modification?