I believe the answer is C. The bonds in the compound magnesium sulfate is ionic and covalent. Magnesium sulfate is soluble in water. When the said compound is dissolved in water, it dissociates into magnesium ions and sulfate ions. However, the bonds that held together the sulfate ions is covalent.
Because it happens somewhere
I believe the answer you're looking for is, D. The motion of atoms and molecules.
Since phosphorus is in the 5th group it has the ability to gain or lose electrons
