考博考试

【单选题】 According to the passage thermal cameras ______.
A．have yet to be put to general use
B．have proved successful since 2 years ago
C．have to undergo tests at least half a year
D．have been playing a dominant role in lie detection

网考网参考答案：A
网考网解析：
由The prototype, ……is at least 2 years from being ready for general use可知正确答案是A(还没有被普遍应用)。 查看试题解析出处>>