Answer: Group 1 would have the lowest electronegativity values.
Explanation:
Electronegativity is the power of an atom in a molecule to attract electrons. It is also synonymous with the oxidizing ability or non-metallic character of elements.
Generally, across a given period from left to right, electronegativity increases due to increasing nuclear charge and decreasing atomic radius ( or atomic size ). This is because there is a greater tendency for a smaller atom with higher nuclear attraction to attract electrons than a larger atom with a lower nuclear attraction due to the shielding effect of the nuclear attraction by the inner shell electrons on the outermost electrons in the larger atom.
Also, down a particular group, electronegativity generally decreases due to increasing atomic radius/size.
This is why metals are generally electropositive ( lose electrons ) and non-metals are electronegative ( gain electrons ) as they are both found more on the left and right sides of the periodic table respectively.