Electronegativity tends to increase from left to right across a row, because A. the shielding effect increases. B. the number of energy levels increases. C. the attraction between the nucleus and the

Electronegativity tends to increase from left to right across a row, because A. the shielding effect increases. B. the number of energy levels increases. C. the attraction between the nucleus and the valence electrons increases. D. the valence electrons are located farther away from the nucleus.