The correct options are
A Ge
B Sn
C Si
The property of self-linking of atoms of an element through covalent bonds to form straight or branched chains and rings of different sizes is called catenation. Down the group, catenation tendency decreses due to decrese in element bond strength. Carbon (C), silicon (Si), germanium (Ge), tin (Sn), lead (Pb) are group- 14 elements.
Catenation tendency is highest in carbon while silicon has second highest tendency of catenation among all elements of family due to higher bond energy. The decreasing tendency of catenation among group 14 elements is as follows:
C>>Si>Ge≈Sn
However, Pb does not show catenation.