Answer:
Group 14
Explanation:
The elements of the Periodic Table are arranged into 18 Groups.
Among the "main group elements" — those in Groups 1, 2 and 13 to 18 — the number of valence electrons — the number of electrons in the outermost energy level — corresponds to the last digit of the Group number.
Thus, Group 14 contains the elements with four valence electrons — C, Si, Ge, Sn, Pb, and Fl.