Total number of isomers of `C_(4)H_(9)Cl` are

Explanation

(i) `CH_(3)-CH_(2)-CH_(2)-CH_(2)-Cl` (ii) `CH_(2)-CH_(2)-underset(Cl)underset(|)(CH)-CH`
(iii) `CH_(3)-overset(CH_(3))overset(|)(CH)-CH_(2)-Cl` (iv) `CH_(2)-underset(Cl)underset(|)overset(CH_(3))overset(|)(C)-CH_(3)`