It is C. because the sunlight bounces off the moon causing it to be visible only at night.
The correct response is C. Chlorine forms 1 covalent bond while Oxygen forms 2 covalent bonds.
1. Common knowledge : Go to the right of periodic table, the atomic radius is decreasing
2. Flurine has 9 protons and lithium has 3 protons. you know that the electron is attracted with the centre of the atom, that's why more proton, more 'energy' that attract to the centre and that's why it make the shape of the atom is smaller
