Six-month-old liliana has been exclusively breast-fed since birth and thus has never had milk from a bottle. the first time liliana is offered a bottle, she tries to suck on it the way she is used to sucking. however, her sucking behavior is not successful with the bottle. she thus has to adapt her sucking in order to get sufficient milk from the bottle. liliana's new understanding of how to suck on the bottle is an indication that she has engaged in the process of

Before they can be published, scientific papers must be peer-reviewed. this means that: a) some other scientific experts read the papers and guarantee that they are true.b) some other scientific experts read the papers and provide quality control by eliminating many mistakes.c) an editor reads the papers, to make sure that all the semicolons are in the correct places.d) everyone in the world is given the opportunity to comment on the papers through a specially maintainedblog.e) government bureaucrats read the papers, to be sure that the papers do not insult the political positions ofthe current officeholders.