Which of the following could be optically active?

Optically activity is the property of certain dissymmetric compounds containing
one or more asymmetric or chiral carbon atoms to rotate the plane of polarized light
clock wise (or) anticlock wise.
The compound is called optically active compound.
option (1) ${\mathrm{CH}}_3-\underset{\underset{\mathrm{Cl}}{|}}{\mathrm{C}}\mathrm{H}-{\mathrm{CH}}_3$  is symmetric
option (2) ${\mathrm{CH}}_3-{\mathrm{CH}}_2-\underset{\underset{\mathrm{Br}}{|}}{\mathrm{C}}\mathrm{H}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$  is symmetric
option (3) ${\mathrm{CH}}_3-\underset{\underset{{\mathrm{CH}}_3}{|}}{\mathrm{C}}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$  is symmetric
option (4) ${\mathrm{CH}}_3-\underset{\underset{\mathrm{Br}}{|}}{\overset{*}{\mathrm{C}}}\mathrm{H}-{\mathrm{CH}}_2-{\mathrm{CH}}_3$  is asymmetric and optically active