Identify A,B,C and D in the following flow chart :

Options

A. A-Impurity defect , B-Stoichiometric defects , C-Non-stoichiometric defects , D-Anion excess defects
B. A-Stoichiometric defects ,B- Non-stoichiometric defects , C-Impurity defects , D-Metal excess defects
C. A- Non-stoichiometric defects , B-Stoichiometric defects , C- Impurity defects , D-Cation vacancy
D. A-Impurity defects , B-Stoichiometric defects , C-Metal excess defects , D-Non- stoichiometric defects

Answer

C