Which of the following is linear in shape?

${\mathrm{CO}}_2$ is linear as there are no lone pairs present on C atom which would be responsible for decreasing in bond angle. 
In ${\mathrm{XeF}}_2$, there are 5 pairs of electrons around $\mathrm{Xe}$and thus, its geometry is trigonal bipyramidal. The fluorine atoms occupy linear positions while the three lone pairs occupy equatorial positions. Thus, ${\mathrm{XeF}}_2$ is a linear molecule

Hence, the correct option is C.