It can be inferred that guarana and taurine（ ）.
A、are addictives
B、are likely safe
C、contain high levels of sugar
D、contain high levels of caffeine
【正确答案】：A
【题目解析】：听力原文：The products are sold with a" health halo, " despite having several known and Potentially several unknown ill-effects. The researchers at UC Berkeley’ s Atkins Center found that 21 of the most popular drinks in the category contain high levels of sugar, caffeine, and sodium. Plus, many of them contain guarana, taurine, and ginger extract. Only the latter one can be defined as "likely safe". Patricia Crawford, the study’ s lead author, said that the lack of research into several of those additives was "troubling". She cited as particularly worrisome the minimal knowledge of the possible effects on the children and teenagers who make up a big chunk of the market for the beverages.本题考查瓜拉那和牛磺酸的本质。原文说这些产品带有“健康光环”，尽管有一些已知的和潜在的未知的副作用。这类最受欢迎的饮料中有21种含有高水平的糖、咖啡因和钠。其中许多含有瓜拉那、牛磺酸和生姜提取物。只有后者可以被定义为“可能安全”。该研究的第一作者帕特里夏•克劳福德表示，对其中几种添加剂缺乏研究是“令人不安的”。可知瓜拉那、牛磺酸是添加剂，A项符合题意。
