The answer is C because SiO2 is a network solid (quartz) just like (diamond and graphite) so when you draw it out, its not quite linear at 120, its actually slightly bent and should be at 110.

Furthermore, why is SiO2 tetrahedral? Reason for giant structure of SiO2: In case of SiO2, the size of the silicon atom is much larger than carbon atom. Greater numbers of oxygen atoms can surround silicon atom. But when four oxygen atoms link with one silicon atom then a tetrahedral structure is produced.

Also, what is the shape of silicon dioxide?

It is a 3 dimensional network solid in which each silicon atom is covalently bonded in a tetrahedral manner to 4 oxygen atoms.

What is the Lewis structure for SiO2?

The Lewis structure for SiO2 is fairly straightforward. You will need to create double bonds to acheive octets for all of the atoms. Si is the least electronegative atom and goes at the center of the Lewis structure. For the SiO2 Lewis structure you have a total of 16 valence electrons.