Put the elements in order from the highest electronegativity at the top of your list, to the lowest at the bottom.

germanium (ge)

gallium (ga)

arsenic (as)

bromine (br)

rubidium (rb)

selenium (se)

Explanation:

Electronegativity is defined as the ability of a substance to readily attract an electron.

Smaller is the size of an atom more will be the ability of its protons residing in the nucleus to attract electrons from a donor atom or substance. Whereas larger is the size of an atom more difficulty its nucleus will face to attract electrons from a donor atom.

Also, it is known that when we move from left to right then there will be decrease in the size of elements.

So, elements Ga, Ge, As, Se and Br all belongs to period 4.  And, bromine is the smallest in size. Hence, it will have the highest electronegativity.

On the other hand, rubidium (Rb) is an alkali metal and largest in size out of the rest of given elements. Hence, it will have least electronegativity.

Therefore, we can conclude that order from the highest electronegativity to the lowest at the bottom are as follows.

                          Br > Se > As > Ge > Ga > Rb