Which one of the following is used as an acid flux in metallurgy ?
A. CaO
B. SiO2
C. Na2CO3
D. SO2
List -I List-II (A) Flespar (I) [Ag3SbS3] (B) Asbestos (II) Al2O3 . H2O (C) Pyrargyrite (III) MgSO4 . H2O (D) Diaspore (IV) KAlSi3O3 (V) CaMg3(SiO3)4
A. IV-A V-B II-C I-D
B. IV-A V-B I-C II-D
C. IV-A I-B III-C II-D
D. II-A V-B IV-C I-D