Explanation

(b)
Electronegativity is the tendency to attract the shared pair of electron towards itself. It decreases down the group and increases in period.
Fluorine has highest electronegativity among all existing elements.
Elements Cl > Br > P > Si
Electrone 3.0 2.8 2.1 1.8
gativity
$\therefore$ Electronegativity of Cl is highest among given elements.