Answer:
B- it partially fills its outer energy level with shared electrons from hydrogen
Step-by-step explanation:
The water molecule is formed by two covalent bonds O - H, being H - O - H its structural formula. The oxygen atom has six electrons in the valence shell, so two more electrons are required for it to achieve electronic stability. The hydrogen atom has only one electron, and one more electron is required for its stability (K layer = two electrons). Therefore, in the water molecule there is a pair of electrons between each hydrogen atom and the oxygen atom. Accordingly, we can conclude that in the water molecule oxygen becomes more chemically stable because it partially fills its external energy level with hydrogen shared electrons.