When should metallic framework not be contaminated during the fabrication of a porcelain fused to metal crown:
A. Between bisque stage and glazing stage
B. Between preheat and opaque stages
C. Between opaque and bisque stages
D. Between one opaque and two opaque stages
A. Between bisque stage and glazing stage
B. Between preheat and opaque stages
C. Between opaque and bisque stages
D. Between one opaque and two opaque stages