Correct answer: Oxygen and sulfur have the same number of valence electrons.

Why?:

Oxygen and sulfur are in the same column of the periodic table. They belong to group VIA or group 16. Elements belonging to the same group have similar properties. In the case of sulfur and oxygen, they both have six valence electrons. In effect, they are both capable of accepting two more electrons to have a complete set of eight valence electrons. The valence electrons are responsible for the properties of the elements.

Answering this question:

Write the electron configuration of each of the elements. For sulfur, it is 1s², 2s², 2p⁶, 3s², 3p⁴ because it has 16 electrons. For oxygen, it is 1s², 2s², 2p⁴ because it has 8 electrons. It can be observed that sulfur has 6 electrons in its 3^rd energy level. Oxygen has 6 electrons in its 2^nd energy level. They both have 6 electrons in their valence energy level. With this, both elements are capable of forming 2 bonds with other atoms. Thus, they form compounds with similar molecular structures.

So, oxygen and sulfur form compounds with similar molecular structure because they both have 6 valence electrons.