SiO2 melts at 1920 K, while CO2 sublimes at 195 K. The reason for these different temperatures is:
a. SiO2 has more electrons and stronger London dispersion forces.
b. SiO2 has ionic bonds and CO2 has covalent bonds
c. SiO2 is a network covalent solid, while CO2 is a molecular solid
d. SiO2 molecules are polar, while CO2 molecules are non-polar
e. SiO2 has stronger covalent bonds than CO2