A European option is different from an American option in that:

a-American options have a fixed exercise price; European options' exercise price is set at the average price of the underlying asset during the life of the option.

b-European options tend to be worth more than American options,ceteris paribus.

c-European options can only be exercised at maturity; American options can be exercised prior to maturity.

d-one is traded in Europe and one in traded in the United States.