单选题Which antenna generally has the narrowest first Fresnel zone in both the horizontal and verticalplanes？（）AomnidirectionalBpatchCYagiDsectorEparabolic dish
单选题
Which antenna generally has the narrowest first Fresnel zone in both the horizontal and verticalplanes？（）
A
omnidirectional
B
patch
C
Yagi
D
sector
E
parabolic dish
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