Which row in the table shows how many electrons there could be in the outer shell of an atom of V?

Explanation:

The element V forms acidic oxide so it must be non- metal because oxides of non metal forms acidic oxide like sulphur ( s ) or chlorine ( Cl₂ )

sulphur forms SO₂ or SO₃ . Chlorine forms acidic oxide like Cl₂O₇ , Cl₂O₃ etc

These oxides are covalent compounds .

So V may have 6 or 7 electrons in the outermost orbit .

Hence option D is the right answer.

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.