What is difference between an epidemic and a pandemic?

What is difference between an epidemic and a pandemic?
A) An epidemic is a disease that is restricted to a small area and does not appear to be spreading or becoming more common, whereas a pandemic is a disease that is spreading wider throughout a population.
B) An epidemic is an actual disease, whereas a pandemic is a worldwide human response to treating that disease.
C) An epidemic is a disease in a local region that is widening, whereas a pandemic is a disease that is widening to an international scale.
D) An epidemic is a disease with a fairly low mortality rate, whereas a pandemic has a much higher mortality rate.