Answer: The correct answer is bismuth.
Solution:
Bismuth is the member of group 15 of the periodic table.
Bismuth contains five valence electrons in its valence shell. Which can be seen from its electronic configuration:
[tex][Bi]=[Xe]4f^{14}5d^{10}6s^{2}6p^{3}[/tex]
Where as other three elements are the members of group 14 of the periodic table with three valence electrons in their respective valence shells.