Carbon belongs to Group 14 and the second period. Silicon is a member of Group 14 and the third period. If carbon has an atomic number of 6, silicon has an atomic number of: 

14

The correct answer is option 2. 14.

Since both carbon and silicon are in Group 14 (also called the carbon group), they will have the same number of valence electrons (electrons in the outermost shell), which influences their chemical behavior.

The key to finding silicon's atomic number lies in the difference between their periods. Carbon is in the second period, and silicon is in the third period. Elements in the same group have a predictable increase in their atomic number as you move down the periods.

Here's the reasoning:

Carbon (period 2) has 6 protons (atomic number).

Moving one period down (to period 3) means adding 8 protons (since each period adds 8 new elements).

Therefore, silicon's atomic number is:

6 (protons in carbon) + 8 (protons added moving a period down) = 14

So the answer is 14.