Chemistry - Complete Pblock- Question with Solution | TestHub

Carbon atom have the tendency to link with one another through covalent bonds to form chains because of its tetra valency. This property is called catenation tendency. Carbon shows maximum catenation tendency among its group elements due to its high bond enthalpy. As we go down, the group size increases and electronegativity decreases therefore catenation tendency decreases.
 So,order of catenation tendency is 

$\mathrm{C}>\mathrm{Si}>\mathrm{Ge}\approx \mathrm{Sn}$