问题
单项选择题
Even though the main source of ______ exposure for a majority of the human population is the sun, the artificial tanning from sun beds contributes significantly to the total UV risk.
A．extra violent
B．extra violet
C．ultraviolet
D．ultravirus
答案
参考答案：C
解析：[分析] 形近识别。 ultraviolet紫外线的：ultraviolet light紫外线光。extra violent特别猛烈的：extra violet特别的紫罗兰；ultravirus超显微病毒。