People have grown taller over the last century, with South Korean women shooting up by more than 20cm on average, and Iranian men gaining 16.5cm. A global study looked at the average height of 18-year-olds in 200 countries between 1914 and 2014.

    The results reveal that while Swedes were the tallest people in the world in 1914, Dutch men have risen from 12th place to claim top spot with an average height of 182.5cm. Latvian women, meanwhile, rose from 28th place in 1914 to become the tallest in the world a century later, with an average height of 169.8cm.

    James Bentham, a co-author of the research from Imperial College, London, says that the global trend is likely to be due primarily to improvements in nutrition and healthcare. “An individual’s genetics has a big influence on their height, but once you average over whole populations, genetics plays a less key role,” he added.

    A little extra height brings a number of advantages, says Elio Riboli of Imperial College. “Being taller is associated with longer life expectancy,” he said. “This is largely due to a lower risk of dying of cardiovascular (心血管的) disease among taller people.”

    But while height has increased around the world, the trend in many countries of north and sub-Saharan Africa causes concern, says Riboli. While height increased in Uganda and Niger during the early 20th century, the trend has reversed in recent years, with height decreasing among 18-year-olds.

    “One reason for these decreases in height is the economic situation in the 1980s,” said Alexander Moradi of the University of Sussex. The nutritional and health crises that followed the policy of structural adjustment, he says, led to many children and teenagers failing to reach their full potential in terms of height.

    Bentham believes the global trend of increasing height has important implications. “How tall we are now is strongly influenced by the environment we grew up in,” he said. “If we give children the best possible start in life now, they will be healthier and more productive for decades to come.”

C。根据关键词James Bentham和genetics定位至第三段。该段指出，詹姆斯·边沁认为全球身高增长趋势的主要原因更可能是营养状况和医疗保健的提高。他补充道：“一个人的基因对其身高有很大影响，但一旦把他们的身高平均到整个群体中，基因的作用就不那么重要了。”可见詹姆斯的观点是基因在个体身高中起到的作用超过在群体身高平均值中起到的作用，C项为该观点的同义转述，故答案为C。A项表示基因没有人们想得那么重要，与原文的An individual’s genetics has a big influence on their height相悖，故错误。B项利用nutrition and healthcare作干扰，但原文说的是詹姆斯认为全球身高增长的趋势可能主要是由于营养和医疗保健的改善，并不是说遗传比营养和医疗保健更重要，故B错误。D项在原文中并未提及，故排除。