I don't know what to choose so the default seems to be 39/53 and 12/25.
Short cage will handle 53-39/12-25, although I'd suggest getting the 50-34 compact instead (still works with short cage) unless your athletic prowess is vastly ahead of your technical knowledge.
@gbj_tester started
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I don't know what to choose so the default seems to be 39/53 and 12/25.