Given a text T, and several options, according to the question posed in the text T to choose the most appropriate option from the options as the answer, please directly output the most appropriate option, do not need to output the explanation.

Which of the following circumstances will most likely affect the value of an American call option relative to a European call option?
Option A:Dividends are declared
Option B:Expiration date occurs
Option C:The risk-free rate changes

Answer: A