The strength of an oxyacid $E({OH})_n$; where $E$ is the central atom, depends upon
(a) electronegativity of $E$ but not on oxidation state of $E$
(b) atomic size of $E$ but not on electronegativity of $E$
(c) not on oxidation state of $E$ in oxyacids
(d) atomic size, electronegativity and oxidation state of $E$.