题干

科研工作者将基因型为Bb的某植物幼苗用秋水仙素处理,使其成为四倍体;再将该四倍体产生的配子进行离体培养成幼苗后再用秋水仙素处理使之染色体加倍。根据上述材料,你认为正确的判断组合是           (   )
①最终获得的后代有2种表现型和3种基因型
②上述育种方式包含了多倍体育种和单倍体育种
③最终获得的后代都是纯合子
④第二次秋水仙素处理后得到的植株是可育的

A:①②③

B:①②④

C:①②③④

D:②③④

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B

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    IPhone owners are vainer(虚荣)and spend more on clothes and grooming(仪容)than those who have BlackBerrys and Android phones, new research claims.BlackBerry owners earn the most and are more likely to have long-term relationships, while people with Android handsets are most creative and the best cooks.

    The study, carried out by TalkTalk Mobile, surveyed 2,000 owners of the three major smartphone brands to determine whether the choice of handset was an extension(延伸) of their personality. The study rated users in various walks of life using a point scoring system including personalities, daily habits and the type of industries they work in.

    Other results from the study found that people with an iPhone are more image conscious and generally consider themselves more attractive than those with other handsets. They are most likely to describe themselves as adventurous, bright and are most likely to work in media, publishing and education. They also believe their boss rates them highly. Apple owners also tend to have done more travelling and are the most active on social media sites.

    BlackBerry owners were found to be the least punctual(准时的), but despite putting in the least hours at work they are the most active phone user—sending more texts and making more calls in the average day than any other phone user. They are more social and have more friends overall. They also earn nearly two and a half thousand pounds a year more than other smartphone owners, with an average salary of $27,406. BlackBerry users classed themselves so loud and mainly work in the health, finance or property sectors. They were also found to drink more tea and coffee each day than any other phone user.

    Android owners were found to watch more TV than others and drink the most alcohol—consuming more in an average week than iPhone and BlackBerry drinkers. They have the most jobs in engineering, the government and public services and environmental services. They have the best manners and are more shy and relaxed than their counterparts.

    Dan Meader, Director of Mobile at TalkTalk, said,“Many of us have our mobile phones on us almost constantly so they do become an extension of us in many ways. It's interesting to see then how the choice in handset may reflect different aspects of personality and the results do show some unusual difference