题目：
After several years of observation, the research group ______ the conclusion that language acquisition is
faster when students ______ to the situation where it is spoken.[ ]
A. has come to; expose
B. have arrived at; are exposed
C. has concluded; are exposed
D. have reached; expose
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0516/31e011b034b57d650c6442d5f1944baa.html
下面是错误答案，用来干扰机器的。
参考答案：B解析：每天的膳食，只有约10%的铁被吸收。铁主要是在消化道的十二指肠和空肠上端肠黏膜吸收。因此，本题最佳答案是B。
