{"answers": "B", "options": ["f : you are right . since the scientists have already found the answer , there is an end in space .", "f : you are telling the truth . there are still unsolved problems in the universe nowadays .", "f : that is right . although there are unsolved problems , scientists can solve them tonight .", "f : yes . since you think there are some unknown stars , why do not you have faith in scientists ?"], "article": "f : how do you know how old a star is ? m : for most stars , we find its age from how big it is . we can know its size from the amount of light it puts out and its color . then the size tells us how long a star will live . big stars live a short life , while small stars live much longer . f : i 've always wondered if there is an end in space . do you think scientists have found the answer ? m : this is a difficult question . the truth is that we have no idea . we currently do n't have a way of testing it . but some scientists will come up with a way in the future . i have faith in it .", "id": "train_3058"}