If you'd provide a context to choose it might be answerable more to a point. Else usage can be rather widespread and differentiated.

"akzeptieren" and "annehmen" are basically the same, except that the former is derived from Latin or French (with the ending of -ieren), whereas the latter is originated from the German language. On the other hand, "aufnehmen" tends to have a meaning of "to receive" (like "bekommen"). Reference sites: https://en.wiktionary.org/wiki/-ieren http://dict.leo.org/englisch-deutsch/akzeptieren http://dict.leo.org/englisch-deutsch/annehmen http://dict.leo.org/englisch-deutsch/aufnehmen === Ich wünsche Dir einen schönen Tag.／I wish you a good day.