One important difference between covalent and ionic bonds is that
a. in covalent bonds two atoms share electrons, whereas in ionic bonds one atom gives one or more electrons to the other atom.
b. in ionic bonds both protons and electrons can be shared, whereas in covalent bonds only electrons can be shared.
c. in ionic bonds two atoms share electrons, whereas in covalent bonds one atom gives one or more electrons to the other atom.
d. ionic bonds only occur among water-soluble elements.
e. ionic bonds are much stronger than covalent bonds.