With reference to Pauling's Electronegativity scale, which one of the following options shows the correct order of electronegativity values of elements?

Among the following, which is not according to the property indicated against it?

The correct decreasing order of negative electron gain enthalpy for $$\mathrm{C}, \mathrm{Ca}, \mathrm{Al}, \mathrm{F}$$ and $$\mathrm{O}$$ is

The group number of the element in the periodic table with the electronic configuration $$(\mathrm{n}-1) \mathrm{d}^2 \mathrm{~ns}^2$$. For $$n=4$$ is:

The increasing order of atomic radii of the following group 13 elements is

In the periodic table metals usually used as catalysts belong to