A-A+
The invisible rays of the ______beyond the vio
问题详情
The invisible rays of the ______beyond the violet end are called the ultraviolet rays.
A．speculation
B．spectrum
C．sleet
D．range
参考答案
正确答案：B
解析：B项spectrum“光谱”符合题意。其他三项都与题意不符：speculation猜测，投机；sleet冰雨；range范围。
