The types of hybrid orbitals used by chlorine atom in\[Cl{O^ - },ClO_2^ - ,ClO_3^ - ,ClO_4^ - \]
(A) \[sp,s{p^2},s{p^3} and s{p^3}d\]
(B) \[sp\]And \[sp\]
(C) Only \[s{p^3}\]
(D) Only\[sp\]

Hint:When atoms are joined together in a definite ratio then a molecule is formed. This molecule is more stable as compared to individual atoms. Each molecule has a specific shape, molecular weight and their properties.

Complete step by step answer:
The intermixing of atomic orbitals having almost the same energy in such a way that new orbits are formed, that new orbitals having the same energy. So this equal energy carrying orbital is known as hybrid orbitals and the phenomenon is known as hybridization.
Condition for hybridisation: only valence shell orbitals take part in hybridization.
It is not necessary that incomplete orbitals take part in hybridization, in some cases fully filled orbitals also take part in hybridization.
Hybridization process takes place at the time of bond formation.
In\[Cl{O^ - },ClO_2^ - ,ClO_3^ - ,ClO_4^ - \] hybridization is \[s{p^3}\]in which one s and two p orbital are used in hybridization. The shape of all these molecules is tetrahedral and the bond angle is\[{109^o}.28\].

Hence, option C is the correct option.

Additional information:
Characteristics of hybridization:
The number of hybrid orbital is equal to the total number of pure atomic orbital undergoing hybridisation.A hybrid orbital is always directional in nature.Covalent bond formed by using hybrid orbital is stronger than pure orbital forms covalent orbitals.

Note:
In \[s{p^3}\]hybridization s character is \[25\% \] and p character is\[75\% \]. In \[s{p^3}\]one s and two p orbitals combined with each other.
The hybrid orbital is arranged itself with minimum repulsion and maximum stability of the molecule.When axial overlapping occurs in hybrid orbitals and sigma bond is formed and when side wise overlapping occurs in between hybrid orbital then pi bond is formed.