Among the following, the correct statements about p block elements are
I. The valence shell electronic configuration of all of them is $$ns^2 np^{1-6}$$
II. Only in p block, metals, nonmetals and metalloids are present
III. Halogens have the lowest negative electron gain enthalpy in the respective periods
IV. Noble gases have no tendency to accept an electron and hence they have large negative values of electron gain enthalpy