Column-I		Column-Ii
A)	F-centers	p)	Extra cations present in interstitial sites
B)	Metal excess defect	q)	Some cations are replaced with one of higher valence
C)	Metal deficiency defect	r)	Both cations and anions are missing from lattices
D)	Schottky defects	s)	Electrons trapped in anionic vacancies

	(A)	(B)	(C)	(D)
1)	s	p	q	r
2)	p	q	s	r
3)	s	q	r	p
4)	p	q	r	s