On mixing a certain alkane with chlorine and irradiating it with ultraviolet light, it forms only one monochloroalkane. This alkane could be

Solution :
In neopentane all the $$H$$ atoms are same $$\left( {{1^ \circ }} \right).$$
\[C{{H}_{3}}\underset{\begin{smallmatrix} | \\ \,\,\,C{{H}_{3}} \end{smallmatrix}}{\overset{\begin{smallmatrix} \,\,\,\,\,C{{H}_{3}} \\ | \end{smallmatrix}}{\mathop{-C-}}}\,C{{H}_{3}}\]