the outer most electronic configuration of the most electronegative element is

a- ns²np³

b- ns2np⁴

c- ns²np⁵

d- ns²np⁶

The correct answer is option (c). The outer most configuration of most electronegative element out of the given option is ns²np⁵. Halogens are most electronegative elements. The configuration of halogens is ns²np⁵. 
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